Merge remote-tracking branch 'origin/master' into feat/todo-multi-in-progress

# Conflicts:
#	packages/todo/tool-todo/README.i18n.yaml

packages/client/connection/package.json

@@ -30,6 +30,7 @@
   "license": "BSD-3-Clause",
   "dependencies": {
     "@deepseek-ai/dsh-host-apiproxy": "workspace:^",
+    "@deepseek-ai/dsh-commands": "workspace:^",
     "@deepseek-ai/dsh-llm": "workspace:^",
     "@deepseek-ai/dsh-session": "workspace:^",
     "@deepseek-ai/dsh-tools": "workspace:^"

packages/client/connection/src/client/api.ts

@@ -9,7 +9,7 @@ export type {
   ApiProxy, SessionsApi, SessionSummary, HostApi, EventsApi, MuxFrame, HostFrame,
   ApprovalResponsePayload, QuestionResponsePayload, HistoryEntry, ToolEventView,
   WorkspaceApi, WorkspaceId, WorkspaceView,
-  CommandsApi, CommandDescriptor, CommandExecuteResult, SkillsApi, SkillEntry,
+  CommandsApi, CommandDescriptor, SkillsApi, SkillEntry,
   ModelCatalogFailure, ModelCatalogModel, ModelProviderGroup, ModelReasoning,
   ModelReasoningEffort, ModelTarget, SessionModels,
 } from '@deepseek-ai/dsh-host-apiproxy/api'

packages/client/connection/src/client/fixture.ts

@@ -7,6 +7,9 @@
 
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
 import type { SessionEvent, SessionId, TodoItem } from '@deepseek-ai/dsh-session/types'
+// Type-only: the brand constructor is host-side; the fixture casts at its
+// wire-fabrication boundary (the schema layer's one-cast-point posture).
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type {
   ApiProxy, ClientRequest, ClientResponse, HistoryEntry, HostFrame, MuxFrame, RpcReceipt,
   ModelTarget, RpcRequest, RpcResponse, RpcResult, ServerRequest, ServerResponse, SessionSummary,
@@ -274,18 +277,27 @@ function viewFor(event: SessionEvent, log: readonly SessionEvent[]): ToolEventVi
   return undefined
 }
 
-/** Fold the latest fixture title into the host's control-frame projection. */
-function titleFrameOf(id: SessionId, log: readonly SessionEvent[]): Extract<MuxFrame, { type: 'session/title' }> | undefined {
-  const event = log.findLast(item => (item as { type: string }).type === 'session/title')
-  if (event === undefined) return undefined
-  const titleEvent = event as unknown as { seq: number; time: number; data: { title: string } }
-  return {
-    type: 'session/title',
-    sessionId: id,
-    title: titleEvent.data.title,
-    eventSeq: titleEvent.seq,
-    updatedAt: titleEvent.time,
+/** Fixture parallel of the host's projection units: whole current values per key over the full log. */
+function projectionValuesOf(log: readonly SessionEvent[]): Record<string, unknown> {
+  const values: Record<string, unknown> = {}
+  const titleEvent = log.findLast(item => (item as { type: string }).type === 'session/title')
+  if (titleEvent !== undefined) {
+    values['title'] = (titleEvent as unknown as { data: { title: string } }).data.title
   }
+  const todos = backscanTodos(log)
+  if (todos !== undefined) values['todos'] = todos
+  return values
+}
+
+/** Host push-frame parallel: emit one session/projection frame per key the given event advanced. */
+function projectionFramesOf(id: SessionId, log: readonly SessionEvent[], event: SessionEvent): Extract<MuxFrame, { type: 'session/projection' }>[] {
+  const type = (event as { type: string }).type
+  const key = type === 'session/title' ? 'title' : type === 'todo/write' ? 'todos' : undefined
+  if (key === undefined) return []
+  const values = projectionValuesOf(log)
+  /* v8 ignore next -- the advancing event is in the log, so its key always has a value. */
+  if (!Object.hasOwn(values, key)) return []
+  return [{ type: 'session/projection', sessionId: id, key, value: values[key], seq: event.seq }]
 }
 
 /**
@@ -515,10 +527,8 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
     emitMux(view === undefined
       ? { type: 'session/event', sessionId: id, event }
       : { type: 'session/event', sessionId: id, event, view })
-    if ((event as { type: string }).type === 'session/title') {
-      // The raw title is already in this log, so the latest-title fold must find it.
-      emitMux(titleFrameOf(id, log) as Extract<MuxFrame, { type: 'session/title' }>)
-    }
+    // Host eager-drive parallel: a unit-advancing event pushes its finished value.
+    for (const frame of projectionFramesOf(id, log, event)) emitMux(frame)
   }
 
   /** At most one in-flight replay per session; cancel clears it. */
@@ -671,14 +681,18 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
         const log = logs.get(request.payload.sessionId) ?? []
         // Snapshot at request time, deliver after the transit delay (mirrors a real host under latency).
         const page = pageOf(log, request.payload.beforeSeq, request.payload.maxMessages ?? 50)
-        // Tail page carries the session-level todo projection (host parallel: full-log backscan).
-        const todos = request.payload.beforeSeq === undefined ? backscanTodos(log) : undefined
+        // Tail page carries the projections block (host parallel: one consistent
+        // cut over the registered units; asOfSeq = window tail seq, -1 on an
+        // empty log — the host's session.seq-1 convention).
+        const projections = request.payload.beforeSeq === undefined
+          ? { asOfSeq: log.length - 1, values: projectionValuesOf(log) }
+          : undefined
         const doomed = failNextHistory
         failNextHistory = false
         const delay = historyDelayMs
         if (delay > 0) await new Promise(resolve => setTimeout(resolve, delay))
         if (doomed) throw new Error('fixture: simulated history transport failure')
-        return ok(request, { ...page, ...todos === undefined ? {} : { todos } })
+        return ok(request, { ...page, ...projections === undefined ? {} : { projections } })
       },
       models: request => ok(request, {
         current: modelTargets.get(request.payload.sessionId)
@@ -883,25 +897,29 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
           ],
         })
       },
+      // Pure admission, mirroring the host: an admitted command logs the
+      // command/run + command/done lifecycle pair (mux-broadcast by append),
+      // and the response only reports resolution.
       execute: (request) => {
         const missing = requireSession(request)
         if (missing !== undefined) return missing
-        const line = request.payload.line.trim()
-        const match = /^\/(\S+)(?:\s+(.*))?$/.exec(line)
+        const id = request.payload.sessionId
+        // Structured split mirroring the host parser: name + verbatim rawInput
+        // (separator whitespace included) — the run payload carries no line.
+        const match = /^\/(\S+)((?:\s.*)?)$/.exec(request.payload.line.trim())
         const name = match?.[1]
-        if (name === 'compact' || name === 'echo') {
-          return ok(request, {
-            matched: true as const,
-            result: { kind: 'success' as const, text: name === 'echo' ? (match?.[2] ?? '') : 'fixture：已压缩（假动作）' },
-          })
+        const args = match?.[2] ?? ''
+        const outcomes: Record<string, string> = {
+          compact: 'fixture：已压缩（假动作）',
+          echo: args.trim(),
+          'goal-fixture': `fixture：goal 已设置（${id}）`,
         }
-        if (name === 'goal-fixture') {
-          return ok(request, {
-            matched: true as const,
-            result: { kind: 'success' as const, text: `fixture：goal 已设置（${request.payload.sessionId}）` },
-          })
-        }
-        return ok(request, { matched: false as const })
+        const text = name === undefined ? undefined : outcomes[name]
+        if (name === undefined || text === undefined) return ok(request, { matched: false as const })
+        const commandId = `fx-cmd-${logOf(id).length}` as CommandId
+        append(id, { type: 'command/run', data: { commandId, name, args, source: { kind: 'user' } } })
+        append(id, { type: 'command/done', data: { commandId, kind: 'success', ...text === '' ? {} : { text } } })
+        return ok(request, { matched: true as const, commandId })
       },
     },
     skills: {
@@ -924,9 +942,13 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
         // Open baseline: subscribed sessions + pending interactions replayed with stable rpcIds.
         for (const s of sessions) {
           if (!s.running) continue
-          conn.push({ rpcId: mint(), payload: { type: 'session/subscribed', sessionId: s.sessionId, lastSeq: (logs.get(s.sessionId)?.length ?? 0) - 1 } })
-          const title = titleFrameOf(s.sessionId, logs.get(s.sessionId) ?? [])
-          if (title !== undefined) conn.push({ rpcId: mint(), payload: title })
+          const log = logs.get(s.sessionId) ?? []
+          conn.push({ rpcId: mint(), payload: { type: 'session/subscribed', sessionId: s.sessionId, lastSeq: log.length - 1 } })
+          // Post-subscribe projection baseline (host parallel: recomputed unit values ride push frames).
+          const values = projectionValuesOf(log)
+          for (const key of Object.keys(values)) {
+            conn.push({ rpcId: mint(), payload: { type: 'session/projection', sessionId: s.sessionId, key, value: values[key], seq: log.length - 1 } })
+          }
         }
         conn.push({
           rpcId: pendingApprovalRpcId,

packages/client/connection/src/client/index.ts

@@ -14,7 +14,7 @@ export type {
   ApiProxy, SessionsApi, SessionSummary, HostApi, EventsApi, MuxFrame, HostFrame,
   ApprovalResponsePayload, QuestionResponsePayload, HistoryEntry, ToolEventView,
   ToolCallView, ToolResultView, WorkspaceApi, WorkspaceId, WorkspaceView,
-  CommandsApi, CommandDescriptor, CommandExecuteResult, SkillsApi, SkillEntry,
+  CommandsApi, CommandDescriptor, SkillsApi, SkillEntry,
   ModelCatalogFailure, ModelCatalogModel, ModelProviderGroup, ModelReasoning,
   ModelReasoningEffort, ModelTarget, SessionModels,
   RpcRequest, RpcResponse, RpcResult, RpcError, RpcErrorCode,

packages/client/connection/tests/fake-api.ts

@@ -1,8 +1,9 @@
 // Test-local programmable IApiClient fake (NOT the fixture: fixture is a demo
 // data source on a real clock; behavior tests need per-case responses and
 // deferred-controlled timing). Streams are hand pumps: pushMux/pushHost.
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type {
-  CommandDescriptor, CommandExecuteResult, HostFrame, IApiClient, ModelTarget, MuxFrame,
+  CommandDescriptor, HostFrame, IApiClient, ModelTarget, MuxFrame,
   RpcRequest, RpcResponse, SessionId, SessionModels, SkillEntry,
 } from '../src/client/api.ts'
 import { RpcId } from '../src/client/api.ts'
@@ -110,10 +111,12 @@ export class FakeApiClient implements IApiClient {
 
   // Payloads stay `unknown` (lint-lane note above); response rows are the real
   // wire shapes so cases can program catalogs and skill lists without casts.
-  onCommandList: (payload: unknown) => Promise<RpcResponse<{ commands: CommandDescriptor[] }>> = () => Promise.resolve(ok({ commands: [] }))
-  onCommandExecute: (payload: unknown) => Promise<RpcResponse<{ matched: boolean; result?: CommandExecuteResult }>> =
-    () => Promise.resolve(ok({ matched: false }))
-  onSkillList: (payload: unknown) => Promise<RpcResponse<{ skills: SkillEntry[] }>> = () => Promise.resolve(ok({ skills: [] }))
+  onCommandList: (payload: unknown) => Promise<RpcResponse<{ commands: CommandDescriptor[] }>>
+    = () => Promise.resolve(ok({ commands: [] }))
+  onCommandExecute: (payload: unknown) => Promise<RpcResponse<{ matched: boolean; commandId?: CommandId }>>
+    = () => Promise.resolve(ok({ matched: false }))
+  onSkillList: (payload: unknown) => Promise<RpcResponse<{ skills: SkillEntry[] }>>
+    = () => Promise.resolve(ok({ skills: [] }))
 
   readonly commands: IApiClient['commands'] = {
     list: (payload: unknown) => this.record('command.list', payload, this.onCommandList(payload)),

packages/client/connection/tests/fixture-commands.spec.ts

@@ -36,20 +36,37 @@ describe('createFixtureApi commands/skills', () => {
     expect(response.result).toMatchObject({ ok: false, error: { code: 'session-not-found' } })
   })
 
-  it('executes a known command line and reports matched with a result', async () => {
+  it('executes a known command line: pure admission plus a mux-broadcast lifecycle pair', async () => {
     const api = createFixtureApi()
+    const frames: unknown[] = []
+    const abort = new AbortController()
+    const stream = api.events.mux(req({}), abort.signal)
+    const pump = (async () => {
+      for await (const frame of stream) {
+        frames.push(frame.payload)
+        if (frames.filter(f => (f as { type: string }).type === 'session/event').length >= 2) abort.abort()
+      }
+    })()
     const response = await api.commands.execute(req({ sessionId: sid('fx-alpha'), line: '/echo hello world' }), signal)
     if (!response.result.ok) throw new Error('execute failed')
-    expect(response.result.value.matched).toBe(true)
-    expect(response.result.value.result).toEqual({ kind: 'success', text: 'hello world' })
+    expect(response.result.value).toMatchObject({ matched: true })
+    expect(response.result.value.commandId).toBeTruthy()
+    await pump
+    const events = frames
+      .filter((f): f is { type: string; event: { type: string; data: Record<string, unknown> } } => (f as { type: string }).type === 'session/event')
+      .map(f => f.event)
+    expect(events).toMatchObject([
+      { type: 'command/run', data: { name: 'echo', args: ' hello world', source: { kind: 'user' } } },
+      { type: 'command/done', data: { kind: 'success', text: 'hello world' } },
+    ])
+    expect(events[0]?.data.commandId).toBe(events[1]?.data.commandId)
   })
 
-  it('addresses execute to the session (result text carries the id)', async () => {
+  it('addresses execute to the session; an unknown session errs', async () => {
     const api = createFixtureApi()
     const hit = await api.commands.execute(req({ sessionId: sid('fx-alpha'), line: '/goal-fixture ship' }), signal)
     if (!hit.result.ok) throw new Error('execute failed')
     expect(hit.result.value.matched).toBe(true)
-    expect(hit.result.value.result?.text).toContain('fx-alpha')
 
     const missing = await api.commands.execute(req({ sessionId: sid('fx-nope'), line: '/goal-fixture ship' }), signal)
     expect(missing.result).toMatchObject({ ok: false, error: { code: 'session-not-found' } })
@@ -60,8 +77,8 @@ describe('createFixtureApi commands/skills', () => {
     for (const line of ['/nope', 'plain text', '/']) {
       const response = await api.commands.execute(req({ sessionId: sid('fx-alpha'), line }), signal)
       if (!response.result.ok) throw new Error('execute failed')
-      expect(response.result.value.matched).toBe(false)
-      expect(response.result.value.result).toBeUndefined()
+      // Pure admission value: the matched bit is the whole response shape.
+      expect(response.result.value).toEqual({ matched: false })
     }
   })
 

packages/client/connection/tests/fixture.spec.ts

@@ -65,13 +65,11 @@ describe('createFixtureApi', () => {
     const clamped = await api.sessions.history(req({ sessionId: sid('fx-alpha'), beforeSeq: -5, maxMessages: 10 }))
     if (!clamped.result.ok) throw new Error('clamped failed')
     expect(clamped.result.value.events).toEqual([])
-    // Unknown session: empty page, not an error (history of a bare id).
+    // Unknown session: empty page, not an error (history of a bare id). The
+    // tail block still rides it — empty-log cut at -1, the host convention.
     const empty = await api.sessions.history(req({ sessionId: sid('no-such'), maxMessages: 10 }))
     if (!empty.result.ok) throw new Error('empty failed')
-    expect(empty.result.value).toEqual({
-      events: [],
-      hasMore: false,
-    })
+    expect(empty.result.value).toEqual({ events: [], hasMore: false, projections: { asOfSeq: -1, values: {} } })
   })
 
   it('serves grouped models and keeps a selected target for later history and fixture requests', async () => {
@@ -217,11 +215,13 @@ describe('createFixtureApi', () => {
     const second = await openOnce()
     expect(first[0]?.payload).toMatchObject({ type: 'session/subscribed', sessionId: 'fx-alpha' })
     expect((first[0]?.payload as { lastSeq: number }).lastSeq).toBeGreaterThan(0)
-    expect(first[1]?.payload).toMatchObject({ type: 'session/title', sessionId: 'fx-alpha', title: 'Fixture 历史会话' })
-    expect(first[2]?.payload).toMatchObject({ type: 'approval/requested', toolName: 'dangerous_tool' })
-    expect(second[2]?.rpcId).toBe(first[2]?.rpcId) // stable rpcId across replays (host replay semantics)
-    expect(first[3]?.payload).toMatchObject({ type: 'question/requested', sessionId: 'fx-alpha' })
-    expect(second[3]?.rpcId).toBe(first[3]?.rpcId)
+    // Projection baseline frames follow the subscribed frame (title + todos units).
+    expect(first[1]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'title', value: 'Fixture 历史会话' })
+    expect(first[2]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'todos' })
+    expect(first[3]?.payload).toMatchObject({ type: 'approval/requested', toolName: 'dangerous_tool' })
+    expect(second[3]?.rpcId).toBe(first[3]?.rpcId) // stable rpcId across replays (host replay semantics)
+    expect(first[4]?.payload).toMatchObject({ type: 'question/requested', sessionId: 'fx-alpha' })
+    expect(second[4]?.rpcId).toBe(first[4]?.rpcId)
   })
 
   it('steer with no replay in flight falls through to a fresh queued turn; non-text blocks stringify empty', async () => {
@@ -623,11 +623,11 @@ describe('createFixtureApi', () => {
     hooks.appendTitle('fx-alpha', 'Fixture 修订标题')
     await vi.waitFor(() => {
       expect(seen.some(f => f.type === 'session/event' && JSON.stringify(f.event.data).includes('正常直播'))).toBe(true)
-      expect(seen.some(f => f.type === 'session/title' && f.title === 'Fixture 修订标题')).toBe(true)
+      expect(seen.some(f => f.type === 'session/projection' && f.key === 'title' && f.value === 'Fixture 修订标题')).toBe(true)
     })
     expect(seen.some(f => f.type === 'session/event' && JSON.stringify(f.event.data).includes('静默丢帧'))).toBe(false)
     const rawTitleIndex = seen.findIndex(f => f.type === 'session/event' && (f.event as { type: string }).type === 'session/title')
-    const titleControlIndex = seen.findIndex(f => f.type === 'session/title' && f.title === 'Fixture 修订标题')
+    const titleControlIndex = seen.findIndex(f => f.type === 'session/projection' && f.key === 'title' && f.value === 'Fixture 修订标题')
     expect(titleControlIndex).toBe(rawTitleIndex + 1)
     // But history serves the silent event (the client's repull finds it).
     const repull = await api.sessions.history(req({ sessionId: sid('fx-alpha'), maxMessages: 5 }))

packages/client/connection/tsconfig.json

@@ -15,6 +15,9 @@
     {
       "path": "../../core/session"
     },
+    {
+      "path": "../../ui/commands"
+    },
     {
       "path": "../../util/brand"
     },

packages/client/runtime/package.json

@@ -32,10 +32,13 @@
   "license": "BSD-3-Clause",
   "dependencies": {
     "@deepseek-ai/dsh-client-connection": "workspace:^",
+    "@deepseek-ai/dsh-commands": "workspace:^",
     "@deepseek-ai/dsh-client-ui-slots": "workspace:^",
     "@deepseek-ai/dsh-host-apiproxy": "workspace:^",
     "@deepseek-ai/dsh-llm": "workspace:^",
     "@deepseek-ai/dsh-session": "workspace:^",
+    "@deepseek-ai/dsh-session-projection": "workspace:^",
+    "@deepseek-ai/dsh-session-title": "workspace:^",
     "immer": "^10.1.1",
     "react": "^18.2.0",
     "zustand": "~4.4.7"

packages/client/runtime/src/client/index.ts

@@ -7,6 +7,7 @@ import { SessionsService } from './sessions/service.ts'
 import type { SessionListState } from './sessions/service.ts'
 import { WorkspacesService } from './workspaces/service.ts'
 import type { ConversationSnapshot, RunningToolCall, ToolResultNode } from './sessions/conversation.ts'
+import type { UseProjection } from './sessions/projection-store.ts'
 
 export { SlotsService } from './slots.ts'
 export type { RootOwnerProps } from './slots.ts'
@@ -28,12 +29,17 @@ export type {
   EngineStoreHandle, EngineStoreInstance, ObservableSnapshot, SnapshotStore,
 } from './contract/store.ts'
 export type {
-  AssistantBlock, AssistantMessageNode, CodeSubCall, ComposerPhase, ContextMessageNode, ConversationNode,
+  AssistantBlock, AssistantMessageNode, CodeSubCall, CommandNode, ComposerPhase, ContextMessageNode, ConversationNode,
   ConversationSnapshot, QueuedMessage, RunningToolCall,
   SteeringMessageNode, TodoItem, ToolResultNode, UnknownSurfaceNode, UserMessageNode,
 } from './sessions/conversation.ts'
 export { PendingWait } from './sessions/pending.ts'
 export type { PendingInteraction, PendingKind, PendingPayloads } from './sessions/pending.ts'
+// Projection value store (session-projection RFC, push model): host-computed
+// whole values per key; domains ship projection support with zero client code.
+export type {
+  ProjectionsBaseline, ProjectionValueStore, SessionProjectionMap, UseProjection,
+} from './sessions/projection-store.ts'
 export type { SessionId } from '@deepseek-ai/dsh-client-connection/client'
 
 /** Client-side Cordis context after declaration merging. */
@@ -59,12 +65,16 @@ declare module '@deepseek-ai/dsh-client-ui-slots' {
     useSession: SnapshotSelectorHook<ConversationSnapshot>
     /** The framework-resolved session id (owners never pass it). */
     sessionId: SessionId
+    /** The fifth framework hook seat: key-addressed projection reader (undefined = capability absent). */
+    useProjection: UseProjection
   }
   /** Standard kit for slots that remain mounted while current session changes. */
   interface SessionMaybeStandardProps {
     useSession: MaybeSnapshotSelectorHook<ConversationSnapshot>
     /** Current session id; absent in the no-session state. */
     sessionId: SessionId | undefined
+    /** Key-addressed projection reader; every key reads absent while no session is current. */
+    useProjection: UseProjection
   }
   /** Props injected into every global slot component. */
   interface GlobalStandardProps {

packages/client/runtime/src/client/sessions/conversation.ts

@@ -3,6 +3,7 @@
 // substructures keep their references (the React.memo premise). callId/approvalId stay plain
 // string here (narrow to real brands when convenient).
 
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
 import type { TodoItem } from '@deepseek-ai/dsh-session/types'
 import type {
@@ -120,6 +121,31 @@ export interface UnknownSurfaceNode {
   data: unknown
 }
 
+/**
+ * One slash-command lifecycle folded from the log-only `command/run` /
+ * `command/done` pair (paired by commandId, mirroring tool call↔result).
+ * Log-only events never enter the surface fold, so the FoldAdapter indexes
+ * them separately and merges the nodes into the flow by seq. A window cut
+ * between the pair soft-falls like tool pairs: a done with no in-window run
+ * still builds a node (name/args null), and a run with no done renders as
+ * still executing.
+ */
+export interface CommandNode {
+  kind: 'command'
+  /** Seq of the command/run event; the done event's seq when only the done is in-window. */
+  seq: number
+  /** Unix epoch ms of the anchoring event. */
+  time: number
+  /** Pairing id minted by the host executor. */
+  commandId: CommandId
+  /** Command name (run payload's structured field); null when the run fell outside the window. */
+  name: string | null
+  /** Verbatim rawInput after the name, separator whitespace included (run payload); null when the run fell outside the window. */
+  args: string | null
+  /** Settlement outcome (done payload); null while the command is still executing. */
+  outcome: { kind: 'success' | 'error'; text?: string } | null
+}
+
 /** Finalized conversation node union (kind discriminates; seq is the React key). */
 export type ConversationNode =
   | UserMessageNode
@@ -127,6 +153,7 @@ export type ConversationNode =
   | SteeringMessageNode
   | ContextMessageNode
   | ToolResultNode
+  | CommandNode
   | UnknownSurfaceNode
 
 /**
@@ -243,7 +270,4 @@ export interface ConversationSnapshot {
    */
   blank: boolean
   lastAgentError: string | null
-  /** Current whole-list `todo/write` projection — the tail page's full-log value, then each live
-   *  write (last write wins); empty = the log holds no plan. */
-  todos: readonly TodoItem[]
 }

packages/client/runtime/src/client/sessions/fold-adapter.ts

@@ -8,8 +8,9 @@ import type { SessionEvent } from '@deepseek-ai/dsh-session/types'
 // go through it — the package root points at lib/index.js (needs a build) which the vite
 // browser bundle cannot resolve; surface.ts has no Node dependencies.
 import { SurfaceManager, isSurfaceEligibleType } from '@deepseek-ai/dsh-session/surface'
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type { ToolCallView, ToolEventView, ToolResultView } from '@deepseek-ai/dsh-client-connection/client'
-import type { ConversationNode } from './conversation.ts'
+import type { CommandNode, ConversationNode } from './conversation.ts'
 import { toAssistantBlocks } from './conversation.ts'
 
 /** In-window tool/call index entry (result-card backfill + runningCalls material). */
@@ -99,6 +100,15 @@ export class FoldAdapter {
   private callIdx = new Map<string, CallIndexEntry>()
   /** Wire result views keyed by the tool/result event's seq (views ride the envelope, not the event). */
   private resultViews = new Map<number, ToolResultView>()
+  /**
+   * Command lifecycle nodes by commandId (insertion = run order). The
+   * `command/run`/`command/done` pair is log-only, so the surface fold never
+   * emits it; this index folds the pair (done settles its run's node in
+   * place) and nodes() merges the products into the flow by seq. Window cuts
+   * soft-fall like tool pairs: a done with no in-window run still builds a
+   * node.
+   */
+  private commandIdx = new Map<string, CommandNode>()
   /** Window revision (bumped on reset/append) keying the nodes() result cache: an unchanged
    *  window returns the previous ARRAY reference, not just cached elements — the snapshot's
    *  reference-stability contract (§A.9.4) starts here. */
@@ -128,10 +138,14 @@ export class FoldAdapter {
     this.degraded = false
     this.callIdx = new Map()
     this.resultViews.clear()
+    this.commandIdx = new Map()
     for (let i = 0; i < events.length; i++) {
       const event = events[i]
       /* v8 ignore next -- dense-array guard: i stays within events.length, so the undefined arm needs a sparse array no caller builds. */
-      if (event !== undefined) this.indexCall(event, views?.[i])
+      if (event !== undefined) {
+        this.indexCall(event, views?.[i])
+        this.indexCommand(event)
+      }
     }
   }
 
@@ -145,6 +159,7 @@ export class FoldAdapter {
     this.rev++
     this.padded.push(event)
     this.indexCall(event, view)
+    this.indexCommand(event)
   }
 
   /**
@@ -180,7 +195,23 @@ export class FoldAdapter {
       this.nodeCache.set(seq, node)
       out.push(node)
     }
-    const value = { nodes: out, degraded: this.degraded }
+    // Command nodes fold outside the surface (log-only events); merge by seq.
+    // Both inputs are seq-ascending (surface order and run-index insertion
+    // order share the log order), so one linear merge keeps flow order.
+    let nodes = out
+    if (this.commandIdx.size > 0) {
+      nodes = []
+      const commands = [...this.commandIdx.values()]
+      let next = 0
+      for (const node of out) {
+        for (let cmd = commands[next]; cmd !== undefined && cmd.seq < node.seq; cmd = commands[++next]) {
+          nodes.push(cmd)
+        }
+        nodes.push(node)
+      }
+      for (let cmd = commands[next]; cmd !== undefined; cmd = commands[++next]) nodes.push(cmd)
+    }
+    const value = { nodes, degraded: this.degraded }
     this.nodesResult = { rev: this.rev, value }
     return value
   }
@@ -195,6 +226,36 @@ export class FoldAdapter {
     return seqs
   }
 
+  /** Fold one command lifecycle event into its node (run mints, done settles in place; done-only soft-falls). */
+  private indexCommand(event: SessionEvent): void {
+    // Log-only plugin events: the host-side dsh-commands declaration cannot
+    // enter the client program, so this wire consumer narrows structurally
+    // (the same posture as tool/code-dispatch in session.ts).
+    if ((event.type as string) === 'command/run') {
+      const data = event.data as unknown as { commandId: CommandId; name: string; args: string }
+      this.commandIdx.set(data.commandId, {
+        kind: 'command', seq: event.seq, time: event.time,
+        commandId: data.commandId, name: data.name, args: data.args, outcome: null,
+      })
+      return
+    }
+    if ((event.type as string) !== 'command/done') return
+    const data = event.data as unknown as { commandId: CommandId; kind: 'success' | 'error'; text?: string }
+    const run = this.commandIdx.get(data.commandId)
+    const outcome = { kind: data.kind, ...data.text === undefined ? {} : { text: data.text } }
+    if (run === undefined) {
+      // Cross-window cut: the run page fell out of the window — build the
+      // node from the done alone (same soft-fall as a call-less tool result).
+      this.commandIdx.set(data.commandId, {
+        kind: 'command', seq: event.seq, time: event.time,
+        commandId: data.commandId, name: null, args: null, outcome,
+      })
+      return
+    }
+    // Settle in place: a fresh node object (published references stay immutable).
+    this.commandIdx.set(data.commandId, { ...run, outcome })
+  }
+
   private indexCall(event: SessionEvent, view?: ToolEventView): void {
     if (event.type === 'tool/result') {
       if (view?.for === 'result') this.resultViews.set(event.seq, view.view)

packages/client/runtime/src/client/sessions/manager.ts

@@ -9,7 +9,12 @@ import { transportError } from '@deepseek-ai/dsh-host-apiproxy/api'
 import { mergeOrderedBaseline } from '../ordered-baseline.ts'
 import type { SessionListEntry, TitledSessionSummary } from './lineage.ts'
 import { flattenLineage } from './lineage.ts'
+// Type-only merge edge: the title domain's client-namespace outlet declares
+// the 'title' projection key this manager projects into list rows (and any
+// useProjection('title') consumer reads). Zero value imports by construction.
+import type {} from '@deepseek-ai/dsh-session-title/client'
 import { Notifier } from './notifier.ts'
+import { ProjectionValueStore } from './projection-store.ts'
 import { Session } from './session.ts'
 
 /**
@@ -43,12 +48,6 @@ type SessionListMutation =
 /** Per-session cap for pre-instantiation approval/question buffering (low-frequency frames; a few dozen covers any real backlog). */
 const PENDING_BUFFER_CAP = 32
 
-/** Latest title control snapshot retained independently of list/instance arrival. */
-interface SessionTitleSnapshot {
-  title: string
-  eventSeq: number
-  updatedAt: number
-}
 
 /** Instance cluster + frame entry + the session list (see the web client architecture RFC). */
 export class SessionManager {
@@ -58,7 +57,11 @@ export class SessionManager {
    *  drop-and-backfill path; replayed and cleared on instantiation. Bounded per session (these
    *  frames are low-frequency; overflow drops oldest) and dropped on session-removed (audit S7). */
   private readonly pendingBuffers = new Map<SessionId, RpcRequest<MuxFrame>[]>()
-  private readonly titleSnapshots = new Map<SessionId, SessionTitleSnapshot>()
+  /** Per-session projection value stores, retained independently of instance arrival (the
+   *  title-snapshot precedent, generalized): push frames land here whether or not the Session
+   *  is instantiated (list rows read the 'title' key), and an instantiated Session adopts the
+   *  same store so history-baseline seeding and frames converge on one row set. */
+  private readonly projectionStores = new Map<SessionId, ProjectionValueStore>()
   private summaries: SessionSummary[] = []
   private listState: 'idle' | 'loading' | 'error' = 'idle'
   /** Arrival phase; the pending → ready edge fires on the first successful pull (see SessionListPhase). */
@@ -163,9 +166,23 @@ export class SessionManager {
       onEngaged: (engaged) => {
         this.recordMutation({ kind: 'engaged', sessionId: engaged.sessionId })
       },
+      projections: this.projectionStore(sessionId),
     })
   }
 
+  /** Resident per-session projection store (create-on-demand; outlives instantiation). */
+  private projectionStore(sessionId: SessionId): ProjectionValueStore {
+    let store = this.projectionStores.get(sessionId)
+    if (store === undefined) {
+      store = new ProjectionValueStore()
+      // List rows project off store keys (title); any-key changes re-enter
+      // the manager's own batched rebuild channel.
+      store.subscribeAny(() => { this.notifier.markDirty() })
+      this.projectionStores.set(sessionId, store)
+    }
+    return store
+  }
+
   // ---- List surface ----
 
   /** Full refresh via session.list (single-flight: an in-flight call is reused). */
@@ -302,23 +319,20 @@ export class SessionManager {
   handleMuxEnvelope(envelope: RpcRequest<MuxFrame>): void {
     const frame = envelope.payload
     if (frame.type === 'stream/error') return // Controller already treats this as stream failure
-    if (frame.type === 'session/title') {
-      const current = this.titleSnapshots.get(frame.sessionId)
-      if (current !== undefined && current.eventSeq >= frame.eventSeq) return
-      this.titleSnapshots.set(frame.sessionId, {
-        title: frame.title,
-        eventSeq: frame.eventSeq,
-        updatedAt: frame.updatedAt,
-      })
+    if (frame.type === 'session/projection') {
+      // Finished host-computed value: land it in the resident store whether or
+      // not the Session is instantiated (list rows read the 'title' key). The
+      // synchronous markDirty keeps the list snapshot same-tick fresh (the
+      // store's own any-key channel is microtask-batched).
+      this.projectionStore(frame.sessionId).apply(frame.key, frame.value, frame.seq)
       this.notifier.markDirty()
       return
     }
     if (frame.type === 'session/subscribed') {
-      const current = this.titleSnapshots.get(frame.sessionId)
-      if (current !== undefined && current.eventSeq > frame.lastSeq) {
-        this.titleSnapshots.delete(frame.sessionId)
-        this.notifier.markDirty()
-      }
+      // Rows past the host's durable baseline rode state a restart lost; drop
+      // them so last-wins cannot pin a phantom value over recomputed truth.
+      this.projectionStores.get(frame.sessionId)?.truncate(frame.lastSeq)
+      this.notifier.markDirty()
       // New mux-generation baseline: buffered session/queued frames belong to
       // the previous generation and the host is about to resend the live
       // snapshot — drop them, or every reconnect appends a duplicate batch
@@ -377,7 +391,7 @@ export class SessionManager {
         this.recordMutation({ kind: 'remove', sessionId: frame.sessionId })
         this.sessions.get(frame.sessionId)?.handleRemoved() // instance survives (resident-instance rule), only flagged in the snapshot
         this.pendingBuffers.delete(frame.sessionId) // a removed session's buffered frames must not replay on a future instantiation
-        this.titleSnapshots.delete(frame.sessionId)
+        this.projectionStores.delete(frame.sessionId) // removed sessions drop their projection rows with the instance
         return
       }
       case 'host/session-status': {
@@ -402,10 +416,12 @@ export class SessionManager {
 
   private buildListSnapshot(): SessionListSnapshot {
     const merged: TitledSessionSummary[] = this.summaries.map((summary) => {
-      const title = this.titleSnapshots.get(summary.sessionId)
-      return title === undefined
-        ? summary
-        : { ...summary, title: title.title, updatedAt: Math.max(summary.updatedAt, title.updatedAt) }
+      // List rows read the generic 'title' projection key (host-computed unit
+      // value; the bespoke session/title frame is retired).
+      const title = this.projectionStores.get(summary.sessionId)?.get('title')
+      return typeof title === 'string' && title !== ''
+        ? { ...summary, title }
+        : summary
     })
     const fresh = flattenLineage(merged)
     const items = fresh.map((entry) => {

packages/client/runtime/src/client/sessions/projection-store.ts

@@ -0,0 +1,183 @@
+/**
+ * Generic per-session projection value store (session-projection RFC, push
+ * model): the host is the only computation site; the client holds finished
+ * whole values per key — `key → { value, seq }` — seeded by the history tail
+ * page's projections block and updated by `session/projection` push frames,
+ * under the single rule **higher seq wins**. No client-side domain folding
+ * exists: a domain ships projection support with zero client code. Per-key
+ * bare observable faces feed `useProjection` (web-react binds them).
+ */
+import type { SessionProjectionMap } from '@deepseek-ai/dsh-session-projection/types'
+import type { ObservableSnapshot } from '../contract/store.ts'
+import { Notifier } from './notifier.ts'
+
+// The single projection type table, typed end to end (host unit, wire block,
+// client store, React hook) — the interface package's pure-type outlet
+// (`/types`, zero imports), never the package root: the root's dsh-agent →
+// dsh-session chain would drag the host `Context.sessions` merge into the
+// client program (one program must not hold both sides). No second
+// client-side "views" table (user ruling, RFC Alternatives).
+export type { SessionProjectionMap } from '@deepseek-ai/dsh-session-projection/types'
+
+/**
+ * The fifth framework hook seat (session-projection RFC): key-addressed
+ * projection reader delivered through the standard kit. `undefined` uniformly
+ * means capability absent — host unit unmounted, or no baseline/frame has
+ * carried the key yet. The selector overload mirrors useSession (per-key uSES
+ * binding; reference stability holds because a key's value reference changes
+ * only when a frame or baseline lands).
+ */
+export type UseProjection = {
+  <K extends Extract<keyof SessionProjectionMap, string>>(key: K): SessionProjectionMap[K] | undefined
+  <K extends Extract<keyof SessionProjectionMap, string>, S>(
+    key: K,
+    selector: (value: SessionProjectionMap[K] | undefined) => S,
+    eq?: (a: S, b: S) => boolean,
+  ): S
+}
+
+/**
+ * Tail-page projections baseline — structurally identical to the wire's
+ * `SessionProjectionsBlock` (apiproxy api layer), restated here so the
+ * React-free store depends only on the type table, not the wire package's
+ * response vocabulary.
+ */
+export interface ProjectionsBaseline {
+  /** The consistent-cut seq (equals the window tail seq by construction). */
+  asOfSeq: number
+  /** Whole current values by key; a registered key absent here means the capability is absent. */
+  values: Partial<SessionProjectionMap>
+}
+
+/** One key's row: the latest finished value and the seq it is consistent with. */
+interface Row {
+  value: unknown
+  seq: number
+}
+
+/** Per-key notification channel: the bare face plus its batching notifier. */
+interface Channel {
+  face: ObservableSnapshot<unknown>
+  notifier: Notifier
+}
+
+/**
+ * One session's projection values. Framework semantics, uniform across every
+ * key: a baseline seeds rows at its cut, a push frame updates one row, and in
+ * both paths a lower-or-equal seq loses — a replayed frame cannot regress a
+ * value, a stale baseline cannot overwrite a newer frame. A key the store has
+ * never seen reads `undefined` (capability absent). Faces are identity-stable
+ * per key (create-on-demand, cached) so the React side binds each exactly
+ * once; the store-level channel (`subscribeAny`) serves coarse consumers (the
+ * manager's list projection reads the `title` key).
+ */
+export class ProjectionValueStore {
+  private readonly rows = new Map<string, Row>()
+  private readonly channels = new Map<string, Channel>()
+  /** Coarse any-key channel (no snapshot cache to rebuild: reads hit rows directly). */
+  private readonly anyNotifier = new Notifier(() => {})
+
+  /**
+   * Key-addressed bare observable face (the useProjection resolution path).
+   * Always defined — absence is an `undefined` snapshot, never a missing
+   * face, so a component may subscribe before the key ever carries a value.
+   * @param key - projection key.
+   * @returns the identity-stable face for this key.
+   */
+  faceOf(key: string): ObservableSnapshot<unknown> {
+    return this.channel(key).face
+  }
+
+  /**
+   * Current whole value for a key (erased framework read; typed reads go
+   * through `useProjection`'s map lookup).
+   * @param key - projection key.
+   * @returns the value, or undefined while the key is absent.
+   */
+  get(key: string): unknown {
+    return this.rows.get(key)?.value
+  }
+
+  /**
+   * Subscribe to any-key changes (microtask-batched) — the manager's list
+   * rebuild channel.
+   * @param listener - change callback.
+   * @returns the unsubscribe function.
+   */
+  subscribeAny(listener: () => void): () => void {
+    return this.anyNotifier.subscribe(listener)
+  }
+
+  /**
+   * Apply one finished value (the `session/projection` push-frame path).
+   * @param key - projection key.
+   * @param value - whole value computed by the host unit.
+   * @param seq - the unit's watermark at emission.
+   */
+  apply(key: string, value: unknown, seq: number): void {
+    const row = this.rows.get(key)
+    if (row !== undefined && seq <= row.seq) return // higher seq wins; replays and stale frames drop
+    this.rows.set(key, { value, seq })
+    this.changed(key)
+  }
+
+  /**
+   * Seed from a history tail page's projections block: every carried key
+   * lands under the same seq rule as frames; a key the block omits is
+   * capability-absent as of the cut — its row clears unless a newer frame
+   * already superseded the cut (a stale baseline can neither overwrite nor
+   * clear newer values).
+   * @param baseline - the response's projections block.
+   */
+  seed(baseline: ProjectionsBaseline): void {
+    // Erased walk: the framework crosses the open key space; per-key typing
+    // is re-established at the consumer (useProjection's map lookup).
+    const values = baseline.values as Record<string, unknown>
+    for (const key of Object.keys(values)) this.apply(key, values[key], baseline.asOfSeq)
+    for (const [key, row] of this.rows) {
+      if (Object.hasOwn(values, key)) continue
+      if (row.seq > baseline.asOfSeq) continue
+      this.rows.delete(key)
+      this.changed(key)
+    }
+  }
+
+  /**
+   * Drop rows past a mux-generation baseline (`session/subscribed.lastSeq`):
+   * a row claiming knowledge beyond the host's own durable baseline rode
+   * state a restart lost — under last-wins it would wrongly outrank the
+   * host's recomputed (lower-seq) values forever. Durable replay and the next
+   * baseline re-seed whatever truly survived (the title-snapshot precedent,
+   * generalized).
+   * @param lastSeq - the subscribed frame's durable baseline seq.
+   */
+  truncate(lastSeq: number): void {
+    for (const [key, row] of this.rows) {
+      if (row.seq <= lastSeq) continue
+      this.rows.delete(key)
+      this.changed(key)
+    }
+  }
+
+  private changed(key: string): void {
+    this.channels.get(key)?.notifier.markDirty()
+    this.anyNotifier.markDirty()
+  }
+
+  private channel(key: string): Channel {
+    let channel = this.channels.get(key)
+    if (channel === undefined) {
+      // The notifier only batches (no snapshot cache to rebuild: faces read rows directly).
+      const notifier = new Notifier(() => {})
+      channel = {
+        notifier,
+        face: {
+          getSnapshot: () => this.rows.get(key)?.value,
+          subscribe: listener => notifier.subscribe(listener),
+        },
+      }
+      this.channels.set(key, channel)
+    }
+    return channel
+  }
+}

packages/client/runtime/src/client/sessions/service.ts

@@ -301,7 +301,7 @@ export class SessionsService {
         props[name] = undefined
       }
     }
-    return { sessionId: undefined, hooks, props }
+    return { sessionId: undefined, hooks, props } // no projections face: every key reads absent without a session
   }
 
   /** Materialize the standard-props bundle for one session (fails loud on duplicate member names). */
@@ -334,7 +334,14 @@ export class SessionsService {
         props[name] = contributedProps[name]
       }
     }
-    return { sessionId: binding.sessionId, hooks, props }
+    return {
+      sessionId: binding.sessionId,
+      hooks,
+      props,
+      // The useProjection seat: key-addressed bare value faces off the
+      // session's projection store (open key space — never a static roster member).
+      projections: { faceOf: key => binding.session.projections.faceOf(key) },
+    }
   }
 
   /**

packages/client/runtime/src/client/sessions/session.ts

@@ -2,7 +2,7 @@
 
 import type { Context } from 'cordis'
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
-import type { SessionEvent, TodoItem } from '@deepseek-ai/dsh-session/types'
+import type { SessionEvent } from '@deepseek-ai/dsh-session/types'
 import type {
   HistoryEntry, IApiClient, MuxFrame, RpcError, RpcId, RpcResult,
   SessionId, ToolEventView,
@@ -20,6 +20,8 @@ import { PendingWait } from './pending.ts'
 import { FoldAdapter } from './fold-adapter.ts'
 import { Notifier } from './notifier.ts'
 import { PartialAccumulator } from './partial.ts'
+import { ProjectionValueStore } from './projection-store.ts'
+import type { ProjectionsBaseline } from './projection-store.ts'
 
 /** Messages requested per history page. */
 export const PAGE_MESSAGES = 50
@@ -35,6 +37,12 @@ export interface SessionOptions {
    * (hidden, still reusable by connectWorkspace).
    */
   onEngaged?(session: Session): void
+  /**
+   * Manager-owned projection value store to adopt (frames route through the
+   * manager and values outlive instantiation); omitted, the Session owns a
+   * private store (bare object-layer construction).
+   */
+  projections?: ProjectionValueStore
 }
 
 /** Queue-row preview cap: the dock renders one line, the full content never leaves the host mirror. */
@@ -99,9 +107,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
   private queueCache: { rev: number; value: QueuedMessage[] } | null = null
   private frozenRev = 0
   private nodesCache: { folded: readonly ConversationNode[]; frozenRev: number; value: readonly ConversationNode[] } | null = null
-  /** Current whole-list todo/write projection: each tail history response replaces it (an omitted
-   *  field is the authoritative empty list) and every live write overwrites it. */
-  private todos: readonly TodoItem[] = []
   /** `run_code` sub-dispatches by parent callId (window-derived, like openCalls). Appends
    *  copy-on-write the per-parent array so published snapshot references never mutate. */
   private codeDispatches = new Map<string, readonly CodeSubCall[]>()
@@ -126,6 +131,19 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
   /** subscribed.lastSeq baseline (gap detection; null when no subscribed frame arrived — degrade to the liveBuffer dedup path). */
   private subscribedLastSeq: number | null = null
 
+  /**
+   * Per-session projection value store (session-projection RFC, push model):
+   * finished whole values computed on the host, seeded by the tail page's
+   * projections block and updated by `session/projection` frames under the
+   * one higher-seq-wins rule. Keys are read via `projections.faceOf(key)`
+   * (the useProjection resolution face); the conversation snapshot never
+   * carries projection values, and no client-side domain folding exists.
+   * Manager-owned when constructed through SessionManager (frames route and
+   * the store outlives instantiation, the title-snapshot precedent); a bare
+   * construction gets a private store.
+   */
+  readonly projections: ProjectionValueStore
+
   private snapshotCache: ConversationSnapshot
   private readonly notifier = new Notifier(() => {
     this.snapshotCache = this.buildSnapshot()
@@ -149,6 +167,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
     private readonly api: IApiClient,
     private readonly options: SessionOptions = {},
   ) {
+    this.projections = options.projections ?? new ProjectionValueStore()
     this.snapshotCache = this.buildSnapshot()
   }
 
@@ -482,13 +501,13 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
         this.openError = result.error
         return
       }
-      this.installWindow(result.value.events, result.value.hasMore, result.value.todos)
+      this.installWindow(result.value.events, result.value.hasMore, result.value.projections)
       // Gap detection (§D.3-4): baseline past the window tail and liveBuffer did not cover it -> pull the tail page once more.
       const tailSeq = this.windowTailSeq()
       if (this.subscribedLastSeq !== null && tailSeq !== null && this.subscribedLastSeq > tailSeq) {
         result = (await this.api.sessions.history({ sessionId: this.sessionId, maxMessages: PAGE_MESSAGES })).result
         if (generation !== this.openGeneration) return
-        if (result.ok) this.installWindow(result.value.events, result.value.hasMore, result.value.todos)
+        if (result.ok) this.installWindow(result.value.events, result.value.hasMore, result.value.projections)
       }
       this.openState = 'open'
     } catch (error) {
@@ -505,22 +524,18 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
   /** Install the history window + stitch the liveBuffer (seq is the sole dedup key).
    *  Stitching MUST NOT route through acceptLiveEvent: openState is still 'loading' here
    *  (doOpen flips it after install), so recursing would push every buffered event straight
-   *  back into liveBuffer where nothing ever drains it — a silent drop loop (audit S1). */
-  private installWindow(entries: HistoryEntry[], hasMore: boolean, todos: readonly TodoItem[] | undefined): void {
+   *  back into liveBuffer where nothing ever drains it — a silent drop loop (audit S1).
+   *  A carried projections block seeds the value store (higher seq wins, so a stale
+   *  baseline cannot overwrite a newer push frame); the window events themselves are
+   *  never folded — the host is the only computation site. */
+  private installWindow(entries: HistoryEntry[], hasMore: boolean, projections?: ProjectionsBaseline): void {
     this.events = entries.map(e => e.event)
     this.views = entries.map(e => e.view)
     this.baseSeq = this.events[0]?.seq ?? 0
     this.hasMore = hasMore
-    // Session-level projection from the tail page (full-log latest todo/write,
-    // independent of the window); an in-window write below re-derives the same
-    // value, and later live events keep overwriting it. Every caller here is a
-    // tail request (no beforeSeq), which the host answers with the projection
-    // or omits it only when the full log holds no todo/write — so an absent
-    // field is the authoritative empty list, not a missing carrier. Assigning
-    // it clears a plan the log never kept (a write lost to a host crash).
-    this.todos = todos ?? []
     this.foldAdapter.reset(this.events, this.baseSeq, this.views)
     this.rebuildDerivedFromWindow()
+    if (projections !== undefined) this.projections.seed(projections)
     const buffered = this.liveBuffer
     this.liveBuffer = []
     for (const item of buffered) this.appendLive(item.event, item.view)
@@ -569,7 +584,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
       const { result } = await this.api.sessions.history({ sessionId: this.sessionId, maxMessages: PAGE_MESSAGES })
       // Failure or superseded by a full resync: drop — the resync path rebuilds and clears the buffer itself.
       if (result.ok && generation === this.openGeneration && this.openState === 'open') {
-        this.installWindow(result.value.events, result.value.hasMore, result.value.todos)
+        this.installWindow(result.value.events, result.value.hasMore, result.value.projections)
       }
     } catch (error) {
       console.error('[web-runtime] gap repair failed:', error)
@@ -689,10 +704,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
         if (this.openCalls.delete(String(event.data.callId))) this.callsRev++
         return
       }
-      case 'todo/write': {
-        this.todos = event.data.todos
-        return
-      }
       case 'turn/end': {
         // Aborted turns never finalize. The accumulated partial is VALUE, not residue: freeze it
         // into an interrupted terminal node (pulse stops, text survives) instead of deleting it.
@@ -737,10 +748,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
 
   /** Re-derive state (partial/openCalls/frozenNodes) from raw window events after a rebuild — keeps
    *  paging/stitching consistent, and makes the live freeze and the history replay converge on the
-   *  same interrupted nodes (chunks are logged, so the replayed sweep re-freezes identical text).
-   *  todos is deliberately NOT reset: it is session-level (seeded by the tail page's full-log
-   *  projection, not derivable from an arbitrary window). The window always extends to the log
-   *  tail, so an in-window todo/write can only overwrite it with the same latest value. */
+   *  same interrupted nodes (chunks are logged, so the replayed sweep re-freezes identical text). */
   private rebuildDerivedFromWindow(): void {
     this.partial = null
     this.openCalls.clear()
@@ -810,7 +818,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
       promptError: this.promptError,
       blank: this.blankBit,
       lastAgentError: this.lastAgentError,
-      todos: this.todos,
     }
   }
 }

packages/client/runtime/tests/event-script.ts

@@ -40,8 +40,10 @@ export const ev = {
     at(seq, { type: 'step/end', data: { turn, step } }),
   turnEnd: (seq: number, turn: number, reason: 'completed' | 'cancelled' = 'completed'): SessionEvent =>
     at(seq, { type: 'turn/end', data: { turn, reason: { kind: reason } } }),
-  todoWrite: (seq: number, todos: { content: string; status: 'pending' | 'in_progress' | 'completed' }[]): SessionEvent =>
-    at(seq, { type: 'todo/write', data: { todos } }),
+  commandRun: (seq: number, commandId: string, name: string, args = ''): SessionEvent =>
+    at(seq, { type: 'command/run', data: { commandId, name, args, source: { kind: 'user' } } }),
+  commandDone: (seq: number, commandId: string, kind: 'success' | 'error' = 'success', text?: string): SessionEvent =>
+    at(seq, { type: 'command/done', data: { commandId, kind, ...text === undefined ? {} : { text } } }),
 }
 
 /** One complete plain turn (turn/start → user → step → assistant → turn/end), 6 events from startSeq. */

packages/client/runtime/tests/fake-api.ts

@@ -1,8 +1,9 @@
 // Test-local programmable IApiClient fake (NOT the fixture: fixture is a demo
 // data source on a real clock; behavior tests need per-case responses and
 // deferred-controlled timing). Streams are hand pumps: pushMux/pushHost.
+import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type {
-  ClientResponse, CommandDescriptor, CommandExecuteResult, HostFrame, IApiClient, ModelTarget, MuxFrame,
+  ClientResponse, CommandDescriptor, HostFrame, IApiClient, ModelTarget, MuxFrame,
   RpcError, RpcReceipt, RpcRequest, RpcResponse, SessionId, SessionModels, SkillEntry,
   WorkspaceId, WorkspaceView,
 } from '@deepseek-ai/dsh-client-connection/client'
@@ -63,7 +64,7 @@ export class FakeApiClient implements IApiClient {
   onCreate: (payload: unknown) => Promise<RpcResponse<{ sessionId: SessionId }>> = () => Promise.resolve(ok({ sessionId: 'fk-new' as SessionId }))
   readonly defaultModel: ModelTarget = { provider: 'deepseek', model: 'deepseek-v4-flash' }
   onHistory: (payload: { sessionId: SessionId; beforeSeq?: number; maxMessages?: number })
-  => Promise<RpcResponse<{ events: never[]; hasMore: boolean; todos?: { content: string; status: 'pending' | 'in_progress' | 'completed' }[] }>> =
+  => Promise<RpcResponse<{ events: never[]; hasMore: boolean }>> =
     () => Promise.resolve(ok({ events: [], hasMore: false }))
 
   onModels: (payload: unknown) => Promise<RpcResponse<SessionModels>> = () => Promise.resolve(ok({
@@ -136,10 +137,12 @@ export class FakeApiClient implements IApiClient {
   // Payloads stay `unknown` (lint-lane note above); response rows are the real
   // wire shapes so cases can program requires-bearing catalogs and dual-address
   // skill lists without casts.
-  onCommandList: (payload: unknown) => Promise<RpcResponse<{ commands: CommandDescriptor[] }>> = () => Promise.resolve(ok({ commands: [] }))
-  onCommandExecute: (payload: unknown) => Promise<RpcResponse<{ matched: boolean; result?: CommandExecuteResult }>> =
-    () => Promise.resolve(ok({ matched: false }))
-  onSkillList: (payload: unknown) => Promise<RpcResponse<{ skills: SkillEntry[] }>> = () => Promise.resolve(ok({ skills: [] }))
+  onCommandList: (payload: unknown) => Promise<RpcResponse<{ commands: CommandDescriptor[] }>>
+    = () => Promise.resolve(ok({ commands: [] }))
+  onCommandExecute: (payload: unknown) => Promise<RpcResponse<{ matched: boolean; commandId?: CommandId }>>
+    = () => Promise.resolve(ok({ matched: false }))
+  onSkillList: (payload: unknown) => Promise<RpcResponse<{ skills: SkillEntry[] }>>
+    = () => Promise.resolve(ok({ skills: [] }))
 
   readonly commands: IApiClient['commands'] = {
     list: (payload: unknown) => this.record('command.list', payload, this.onCommandList(payload)),

packages/client/runtime/tests/fold-adapter.spec.ts

@@ -142,4 +142,75 @@ describe('FoldAdapter', () => {
     const node = adapter.nodes().nodes[0]
     expect(node).toMatchObject({ kind: 'tool-result', call: null, callView: null, resultView: { title: '孤儿' } })
   })
+
+  describe('command lifecycle nodes', () => {
+    it('folds a run/done pair into one settled node merged into flow order by seq', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([
+        ev.user(0, '先说话'),
+        ev.commandRun(1, 'cmd-1', 'plan'),
+        ev.commandDone(2, 'cmd-1', 'success', '已进入 plan mode'),
+        ev.assistant(3, 0, '然后回答'),
+      ], 0)
+      const { nodes } = adapter.nodes()
+      expect(nodes.map(n => [n.kind, n.seq])).toEqual([['user', 0], ['command', 1], ['assistant', 3]])
+      expect(nodes[1]).toMatchObject({
+        kind: 'command', commandId: 'cmd-1', name: 'plan', args: '',
+        outcome: { kind: 'success', text: '已进入 plan mode' },
+      })
+    })
+
+    it('renders a run with no done as still executing (outcome null)', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([ev.commandRun(0, 'cmd-2', 'goal', ' ship it')], 0)
+      expect(adapter.nodes().nodes[0]).toMatchObject({
+        kind: 'command', name: 'goal', args: ' ship it', outcome: null,
+      })
+    })
+
+    it('soft-falls a done-only window into a node built from the done (cross-window cut)', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([ev.commandDone(80, 'cmd-3', 'error', '失败了')], 80)
+      expect(adapter.nodes().nodes[0]).toMatchObject({
+        kind: 'command', seq: 80, commandId: 'cmd-3', name: null, args: null,
+        outcome: { kind: 'error', text: '失败了' },
+      })
+    })
+
+    it('settles a live-appended done in place, keeping the node at the run seq', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset(plainTurn(0, 0, 'q', 'a'), 0)
+      adapter.append(ev.commandRun(6, 'cmd-4', 'clear'))
+      const running = adapter.nodes().nodes.find(n => n.kind === 'command')
+      expect(running).toMatchObject({ outcome: null })
+      adapter.append(ev.commandDone(7, 'cmd-4'))
+      const settled = adapter.nodes().nodes.find(n => n.kind === 'command')
+      expect(settled).toMatchObject({ seq: 6, outcome: { kind: 'success' } })
+      // Settlement replaced the node object rather than mutating the published one.
+      expect(settled).not.toBe(running)
+    })
+
+    it('tails command nodes whose seq is past every surface node', () => {
+      const adapter = new FoldAdapter()
+      adapter.reset([ev.user(0, '问'), ev.commandRun(1, 'cmd-tail', 'plan')], 0)
+      expect(adapter.nodes().nodes.map(n => n.kind)).toEqual(['user', 'command'])
+    })
+
+    it('command nodes survive the degraded linear-scan branch', () => {
+      const adapter = new FoldAdapter()
+      const errorSpy = vi.spyOn(console, 'error').mockImplementation(() => undefined)
+      try {
+        adapter.reset([
+          ev.commandRun(0, 'cmd-5', 'plan'),
+          ev.commandDone(1, 'cmd-5'),
+          at(2, { type: 'assistant/message', surfaceOp: 'bogus-op', data: { turn: 0, step: 0, content: [{ type: 'text', text: '坏 op' }], provenance: { provider: 'x', model: 'y' } } }),
+        ], 0)
+        const { nodes, degraded } = adapter.nodes()
+        expect(degraded).toBe(true)
+        expect(nodes.some(n => n.kind === 'command')).toBe(true)
+      } finally {
+        errorSpy.mockRestore()
+      }
+    })
+  })
 })

packages/client/runtime/tests/manager.spec.ts

@@ -133,21 +133,18 @@ describe('list lifecycle', () => {
     expect(manager.getListSnapshot().items.map(i => i.sessionId)).toEqual([S2])
   })
 
-  it('retains monotonic title snapshots before list arrival, merges recency, and clears them on removal', async () => {
+  it('retains title projections before list arrival, keeps last-wins by seq, and clears them on removal', async () => {
     const api = new FakeApiClient()
     const manager = new SessionManager(api)
-    manager.handleMuxEnvelope({
-      rpcId: 'title-new' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Newest', eventSeq: 4, updatedAt: 300 },
-    })
-    manager.handleMuxEnvelope({
-      rpcId: 'title-stale' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Stale', eventSeq: 3, updatedAt: 900 },
-    })
-    manager.handleMuxEnvelope({
-      rpcId: 'title-equal' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Equal', eventSeq: 4, updatedAt: 901 },
-    })
+    const titleFrame = (rpcId: string, title: string, seq: number) => {
+      manager.handleMuxEnvelope({
+        rpcId: rpcId as never,
+        payload: { type: 'session/projection', sessionId: S1, key: 'title', value: title, seq } as never,
+      })
+    }
+    titleFrame('title-new', 'Newest', 4)
+    titleFrame('title-stale', 'Stale', 3)
+    titleFrame('title-equal', 'Equal', 4)
     api.onList = () => Promise.resolve(ok({
       items: [summary(S1), summary(S2, { updatedAt: 200 })] as never[],
     }))
@@ -155,7 +152,7 @@ describe('list lifecycle', () => {
 
     const titled = manager.getListSnapshot()
     expect(titled.items.map(item => item.sessionId)).toEqual([S1, S2])
-    expect(titled.items[0]).toMatchObject({ title: 'Newest', updatedAt: 300 })
+    expect(titled.items[0]?.title).toBe('Newest')
     expect(titled.items[1]?.title).toBeUndefined()
 
     manager.handleHostEnvelope({ rpcId: 'removed' as never, payload: { type: 'host/session-removed', sessionId: S1 } })
@@ -163,34 +160,27 @@ describe('list lifecycle', () => {
     expect(manager.getListSnapshot().items.find(item => item.sessionId === S1)?.title).toBeUndefined()
   })
 
-  it('drops a retained title beyond the subscription baseline before accepting its durable replay', async () => {
+  it('drops a projection row beyond the subscription baseline before accepting its durable replay', async () => {
     const api = new FakeApiClient()
     api.onList = () => Promise.resolve(ok({ items: [summary(S1)] as never[] }))
     const manager = new SessionManager(api)
     await manager.refreshList()
-    manager.handleMuxEnvelope({
-      rpcId: 'title-unflushed' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Unflushed', eventSeq: 4, updatedAt: 400 },
-    })
+    const frame = (rpcId: string, payload: object) => {
+      manager.handleMuxEnvelope({ rpcId: rpcId as never, payload: payload as never })
+    }
+    frame('title-unflushed', { type: 'session/projection', sessionId: S1, key: 'title', value: 'Unflushed', seq: 4 })
 
-    manager.handleMuxEnvelope({
-      rpcId: 'subscribed-recovered' as never,
-      payload: { type: 'session/subscribed', sessionId: S1, lastSeq: 2 },
-    })
+    // The durable baseline says the host only knows up to seq 2: the phantom
+    // row rode lost state and must drop, or last-wins pins it forever.
+    frame('subscribed-recovered', { type: 'session/subscribed', sessionId: S1, lastSeq: 2 })
     expect(manager.getListSnapshot().items[0]?.title).toBeUndefined()
-    expect(manager.getListSnapshot().items[0]?.updatedAt).toBe(100)
 
-    manager.handleMuxEnvelope({
-      rpcId: 'title-durable' as never,
-      payload: { type: 'session/title', sessionId: S1, title: 'Durable', eventSeq: 2, updatedAt: 200 },
-    })
-    expect(manager.getListSnapshot().items[0]).toMatchObject({ title: 'Durable', updatedAt: 200 })
+    frame('title-durable', { type: 'session/projection', sessionId: S1, key: 'title', value: 'Durable', seq: 2 })
+    expect(manager.getListSnapshot().items[0]?.title).toBe('Durable')
 
-    manager.handleMuxEnvelope({
-      rpcId: 'subscribed-current' as never,
-      payload: { type: 'session/subscribed', sessionId: S1, lastSeq: 2 },
-    })
-    expect(manager.getListSnapshot().items[0]).toMatchObject({ title: 'Durable', updatedAt: 200 })
+    // A baseline at or past the row's seq keeps it (nothing phantom to drop).
+    frame('subscribed-current', { type: 'session/subscribed', sessionId: S1, lastSeq: 2 })
+    expect(manager.getListSnapshot().items[0]?.title).toBe('Durable')
   })
 })
 

packages/client/runtime/tests/projection-store.spec.ts

@@ -0,0 +1,187 @@
+/**
+ * Projection value store (session-projection RFC, push model): the single
+ * higher-seq-wins rule on both paths (a stale baseline cannot overwrite a
+ * newer push frame; a replayed frame cannot regress), capability absence as
+ * undefined, generation truncation, and the Session/manager wiring (tail-page
+ * seeding, session/projection frame routing pre- and post-instantiation, the
+ * list rows' title projection).
+ */
+import { describe, expect, it } from 'vitest'
+import type { SessionId } from '@deepseek-ai/dsh-client-connection/client'
+import { ProjectionValueStore } from '../src/client/sessions/projection-store.ts'
+import { Session } from '../src/client/sessions/session.ts'
+import { SessionManager } from '../src/client/sessions/manager.ts'
+import { FakeApiClient, ok } from './fake-api.ts'
+import { entries, plainTurn } from './event-script.ts'
+
+// Test-domain keys merged into the projection map (the interface package's
+// pure-type outlet), the same way domain host plugins merge theirs.
+declare module '@deepseek-ai/dsh-session-projection/types' {
+  interface SessionProjectionMap {
+    'test/marks': { marks: string[] }
+  }
+}
+
+const SID = 'fk-s1' as SessionId
+
+describe('ProjectionValueStore semantics', () => {
+  it('reads undefined until a value lands (capability absence)', () => {
+    const store = new ProjectionValueStore()
+    expect(store.get('test/marks')).toBeUndefined()
+    expect(store.faceOf('test/marks').getSnapshot()).toBeUndefined()
+  })
+
+  it('applies frames last-wins by seq: replayed and stale frames drop', () => {
+    const store = new ProjectionValueStore()
+    store.apply('test/marks', { marks: ['a'] }, 5)
+    store.apply('test/marks', { marks: ['a', 'b'] }, 9)
+    expect(store.get('test/marks')).toEqual({ marks: ['a', 'b'] })
+    store.apply('test/marks', { marks: ['stale'] }, 5)
+    store.apply('test/marks', { marks: ['equal'] }, 9)
+    expect(store.get('test/marks')).toEqual({ marks: ['a', 'b'] })
+  })
+
+  it('a stale baseline can neither overwrite nor clear a newer frame; a fresh one reseeds and clears', () => {
+    const store = new ProjectionValueStore()
+    store.apply('test/marks', { marks: ['frame-20'] }, 20)
+    // Stale cut: carried key loses to the newer frame; omitted key survives.
+    store.seed({ asOfSeq: 10, values: { 'test/marks': { marks: ['baseline-10'] } } })
+    expect(store.get('test/marks')).toEqual({ marks: ['frame-20'] })
+    store.seed({ asOfSeq: 15, values: {} })
+    expect(store.get('test/marks')).toEqual({ marks: ['frame-20'] })
+    // Fresh cut: carried key reseeds…
+    store.seed({ asOfSeq: 30, values: { 'test/marks': { marks: ['baseline-30'] } } })
+    expect(store.get('test/marks')).toEqual({ marks: ['baseline-30'] })
+    // …and an omitting fresh cut clears (capability absent as of the cut).
+    store.seed({ asOfSeq: 40, values: {} })
+    expect(store.get('test/marks')).toBeUndefined()
+  })
+
+  it('truncate drops rows past the durable baseline and keeps the rest', () => {
+    const store = new ProjectionValueStore()
+    store.apply('test/marks', { marks: ['durable'] }, 5)
+    store.apply('other', 'phantom', 50)
+    store.truncate(10)
+    expect(store.get('test/marks')).toEqual({ marks: ['durable'] })
+    expect(store.get('other')).toBeUndefined()
+  })
+
+  it('notifies the key face on change (batched) and not on dropped applications', async () => {
+    const store = new ProjectionValueStore()
+    let keyTicks = 0
+    let anyTicks = 0
+    store.faceOf('test/marks').subscribe(() => { keyTicks += 1 })
+    store.subscribeAny(() => { anyTicks += 1 })
+    store.apply('test/marks', { marks: ['a'] }, 5)
+    await Promise.resolve()
+    expect(keyTicks).toBe(1)
+    expect(anyTicks).toBe(1)
+    store.apply('test/marks', { marks: ['replay'] }, 3)
+    await Promise.resolve()
+    expect(keyTicks).toBe(1)
+    expect(anyTicks).toBe(1)
+  })
+
+  it('faces are identity-stable per key (the React binding cache premise)', () => {
+    const store = new ProjectionValueStore()
+    expect(store.faceOf('test/marks')).toBe(store.faceOf('test/marks'))
+  })
+})
+
+describe('Session tail-page seeding', () => {
+  it('seeds the store from a history response carrying a projections block', async () => {
+    const api = new FakeApiClient()
+    const session = new Session(SID, api)
+    api.onHistory = () => Promise.resolve(ok({
+      events: entries(plainTurn(0, 0, '问', '答')) as never[], hasMore: false,
+      projections: { asOfSeq: 5, values: { 'test/marks': { marks: ['from-baseline'] } } },
+    } as never))
+    await session.open()
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['from-baseline'] })
+  })
+
+  it('a resync serving a stale block keeps the newer pushed value (seq rule end to end)', async () => {
+    const api = new FakeApiClient()
+    const session = new Session(SID, api)
+    api.onHistory = () => Promise.resolve(ok({
+      events: entries(plainTurn(0, 0, 'a', 'b')) as never[], hasMore: false,
+      projections: { asOfSeq: 5, values: { 'test/marks': { marks: ['baseline'] } } },
+    } as never))
+    await session.open()
+    session.projections.apply('test/marks', { marks: ['pushed-9'] }, 9)
+    await session.resync()
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['pushed-9'] })
+  })
+
+  it('treats a blockless response as no reset: pushed values survive', async () => {
+    const api = new FakeApiClient()
+    const session = new Session(SID, api)
+    api.onHistory = () => Promise.resolve(ok({ events: entries(plainTurn(0, 0, 'a', 'b')) as never[], hasMore: false }))
+    await session.open()
+    session.projections.apply('test/marks', { marks: ['pushed'] }, 9)
+    await session.resync()
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['pushed'] })
+  })
+})
+
+describe('manager frame routing', () => {
+  const sid = (s: string): SessionId => s as SessionId
+
+  it('lands session/projection frames before instantiation and the Session adopts the same store', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    manager.handleMuxEnvelope({
+      rpcId: 'p1' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'test/marks', value: { marks: ['early'] }, seq: 7 } as never,
+    })
+    const session = manager.get(sid('s1'))
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['early'] })
+    // Frames after instantiation land in the same store.
+    manager.handleMuxEnvelope({
+      rpcId: 'p2' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'test/marks', value: { marks: ['later'] }, seq: 9 } as never,
+    })
+    expect(session.projections.get('test/marks')).toEqual({ marks: ['later'] })
+  })
+
+  it('projects the title key into list rows and truncates phantom rows on the subscribed baseline', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    api.onList = () => Promise.resolve(ok({
+      items: [{ sessionId: sid('s1'), updatedAt: 1, running: false, blank: false }],
+    }) as never)
+    await manager.refreshList()
+    manager.handleMuxEnvelope({
+      rpcId: 't1' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'title', value: 'Projected title', seq: 4 } as never,
+    })
+    await Promise.resolve()
+    expect(manager.getListSnapshot().items[0]?.title).toBe('Projected title')
+    // The durable baseline says the host only knows up to seq 2: the row rode
+    // lost state and must drop (the un-flushed title precedent).
+    manager.handleMuxEnvelope({
+      rpcId: 'sub' as never,
+      payload: { type: 'session/subscribed', sessionId: sid('s1'), lastSeq: 2 } as never,
+    })
+    await Promise.resolve()
+    expect(manager.getListSnapshot().items[0]?.title).toBeUndefined()
+  })
+
+  it('drops the projection store with the removed session', async () => {
+    const api = new FakeApiClient()
+    const manager = new SessionManager(api)
+    api.onList = () => Promise.resolve(ok({
+      items: [{ sessionId: sid('s1'), updatedAt: 1, running: false, blank: false }],
+    }) as never)
+    await manager.refreshList()
+    manager.handleMuxEnvelope({
+      rpcId: 't1' as never,
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'title', value: 'Doomed', seq: 4 } as never,
+    })
+    manager.handleHostEnvelope({
+      rpcId: 'rm' as never,
+      payload: { type: 'host/session-removed', sessionId: sid('s1') } as never,
+    })
+    expect(manager.get(sid('s1')).projections.get('title')).toBeUndefined()
+  })
+})

packages/client/runtime/tests/session.spec.ts

@@ -22,9 +22,9 @@ function makeSession(api = new FakeApiClient()): { api: FakeApiClient; session:
   return { api, session: new Session(SID, api) }
 }
 
-function histResponse(events: SessionEvent[], hasMore = false, todos?: { content: string; status: 'pending' | 'in_progress' | 'completed' }[]) {
+function histResponse(events: SessionEvent[], hasMore = false) {
   // history now returns HistoryEntry[] ({event, view?}); these tests are view-less.
-  return Promise.resolve(ok({ events: entries(events) as never[], hasMore, ...todos === undefined ? {} : { todos } }))
+  return Promise.resolve(ok({ events: entries(events) as never[], hasMore }))
 }
 
 describe('open', () => {
@@ -104,6 +104,28 @@ describe('live event path', () => {
     expect(session.getSnapshot().nodes).toEqual(before.nodes)
   })
 
+  it('materializes a command node from live lifecycle frames and reproduces it from a history window', async () => {
+    // Live path: run mints an executing node, done settles it in the flow.
+    const { session } = await opened()
+    const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
+    feed(ev.commandRun(6, 'cmd-live', 'plan'))
+    let command = session.getSnapshot().nodes.at(-1)
+    expect(command).toMatchObject({ kind: 'command', name: 'plan', args: '', outcome: null })
+    feed(ev.commandDone(7, 'cmd-live', 'success', '已进入 plan mode'))
+    command = session.getSnapshot().nodes.at(-1)
+    expect(command).toMatchObject({ kind: 'command', seq: 6, outcome: { kind: 'success', text: '已进入 plan mode' } })
+
+    // Replay path (refresh): the same pair inside the history window folds identically.
+    const replayed = await opened([
+      ...plainTurn(0, 0, 'a', 'b'),
+      ev.commandRun(6, 'cmd-live', 'plan'),
+      ev.commandDone(7, 'cmd-live', 'success', '已进入 plan mode'),
+    ])
+    expect(replayed.session.getSnapshot().nodes.at(-1)).toMatchObject({
+      kind: 'command', seq: 6, name: 'plan', outcome: { kind: 'success', text: '已进入 plan mode' },
+    })
+  })
+
   it('accumulates chunks into partial, then finalize swaps partial out as the node lands', async () => {
     const { session } = await opened()
     const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
@@ -158,42 +180,6 @@ describe('live event path', () => {
     })
   })
 
-  it('folds todo/write into snapshot.todos last-write-wins, live and on window replay', async () => {
-    const listA = [{ content: '搭骨架', status: 'completed' as const }, { content: '写组件', status: 'in_progress' as const }]
-    const listB = [{ content: '搭骨架', status: 'completed' as const }, { content: '写组件', status: 'completed' as const }]
-    const { session } = await opened()
-    expect(session.getSnapshot().todos).toEqual([])
-    const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
-    feed(ev.todoWrite(6, listA))
-    expect(session.getSnapshot().todos).toEqual(listA)
-    feed(ev.todoWrite(7, listB))
-    expect(session.getSnapshot().todos).toEqual(listB)
-    // Window replay converges on the same last snapshot (history contains both writes).
-    const replayed = makeSession()
-    replayed.api.onHistory = () => histResponse([...plainTurn(0, 0, 'a', 'b'), ev.todoWrite(6, listA), ev.todoWrite(7, listB)])
-    await replayed.session.open()
-    expect(replayed.session.getSnapshot().todos).toEqual(listB)
-  })
-
-  it('seeds todos from the tail page projection when the last write precedes the window', async () => {
-    const list = [{ content: '窗口外的计划', status: 'in_progress' as const }]
-    // Cold open: the page window carries NO todo/write; the projection rides the response.
-    const { api, session } = makeSession()
-    api.onHistory = () => histResponse(plainTurn(100, 9, '问', '答'), true, list)
-    await session.open()
-    expect(session.getSnapshot().todos).toEqual(list)
-    // Paging an older window in must not clear the session-level projection.
-    api.onHistory = () => histResponse(plainTurn(94, 8, '旧问', '旧答'), false)
-    await session.loadOlder()
-    expect(session.getSnapshot().todos).toEqual(list)
-    // A later live write still overrides the seeded projection.
-    session.handleMuxEnvelope('r' as never, {
-      type: 'session/event', sessionId: SID,
-      event: ev.todoWrite(106, [{ content: '新计划', status: 'pending' as const }]),
-    })
-    expect(session.getSnapshot().todos).toEqual([{ content: '新计划', status: 'pending' }])
-  })
-
   it('repairs a seq gap by repulling the tail page instead of appending a hole', async () => {
     const { api, session } = await opened(plainTurn(0, 0, 'a', 'b')) // tail seq = 5
     const repaired = [...plainTurn(0, 0, 'a', 'b'), ...plainTurn(6, 1, 'c', 'd')]
@@ -207,37 +193,6 @@ describe('live event path', () => {
     const seqs = session.getSnapshot().nodes.map(n => n.seq)
     expect(seqs).toEqual([1, 3, 7, 9]) // both turns' user/assistant, no hole, no duplicate 9
   })
-
-  it('gap repair adopts the repull response projection (a missed todo/write outside the new tail page)', async () => {
-    const { api, session } = await opened(plainTurn(0, 0, 'a', 'b')) // tail seq = 5
-    expect(session.getSnapshot().todos).toEqual([])
-    // The missed range contained a todo/write that the repulled page no longer
-    // covers; the response's session-level projection is the only carrier.
-    const current = [{ content: '断线期间写的', status: 'in_progress' as const }]
-    api.onHistory = () => histResponse([...plainTurn(0, 0, 'a', 'b'), ...plainTurn(8, 1, 'c', 'd')], false, current)
-    session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event: ev.assistant(11, 1, 'd') })
-    await vi.waitFor(() => {
-      expect(api.callsOf('session.history').length).toBe(2)
-    })
-    await Promise.resolve()
-    expect(session.getSnapshot().todos).toEqual(current)
-  })
-
-  it('clears the plan when a tail response omits the projection (a write the log never kept)', async () => {
-    // Live write lands, then the host crashes before persisting it: the
-    // authoritative log holds no todo/write, so the resync tail response
-    // carries no projection — an omitted field on a tail request is the empty
-    // list, not a missing carrier, and the rolled-back plan must disappear.
-    const { api, session } = await opened(plainTurn(0, 0, 'a', 'b'))
-    session.handleMuxEnvelope('r' as never, {
-      type: 'session/event', sessionId: SID,
-      event: ev.todoWrite(6, [{ content: '丢失的计划', status: 'in_progress' as const }]),
-    })
-    expect(session.getSnapshot().todos).toEqual([{ content: '丢失的计划', status: 'in_progress' }])
-    api.onHistory = () => histResponse(plainTurn(0, 0, 'a', 'b'))
-    await session.resync()
-    expect(session.getSnapshot().todos).toEqual([])
-  })
 })
 
 describe('paging', () => {

packages/client/runtime/tests/sessions-service.spec.ts

@@ -47,7 +47,7 @@ describe('list store projection', () => {
     const b = bench()
     b.svc.handleMuxEnvelope({
       rpcId: 'title' as never,
-      payload: { type: 'session/title', sessionId: sid('s1'), title: 'Durable title', eventSeq: 2, updatedAt: 3 },
+      payload: { type: 'session/projection', sessionId: sid('s1'), key: 'title', value: 'Durable title', seq: 2 } as never,
     })
     await feedList(b, [
       { id: 's1', cwd: '/home/u/proj-a/' },

packages/client/runtime/tsconfig.json

@@ -23,6 +23,15 @@
     {
       "path": "../../host/apiproxy"
     },
+    {
+      "path": "../../ui/commands"
+    },
+    {
+      "path": "../../session-projection/session-projection"
+    },
+    {
+      "path": "../../session-title/session-title"
+    },
     {
       "path": "../../llm/llm"
     },

packages/client/ui-command/src/client/service.ts

@@ -227,7 +227,15 @@ export class CommandService extends Service implements CommandServiceContract {
     }
   }
 
-  /** The command.execute transaction, addressed to the session's agent. */
+  /**
+   * The command.execute transaction, addressed to the session's agent — pure
+   * admission semantics. An unmatched line reports an error outcome (the
+   * composer's immediate admission feedback); an admitted command reports
+   * plain success regardless of its handler outcome, because the host
+   * executor durably logged the lifecycle (`command/run`/`command/done`) and
+   * the outcome renders as a persistent flow node — the composer never
+   * echoes it. Transport failures throw.
+   */
   private async execute(
     session: ClientSessionContext,
     line: string,
@@ -236,25 +244,25 @@ export class CommandService extends Service implements CommandServiceContract {
     const { result } = await connection.api.commands.execute({ sessionId: session.sessionId, line })
     if (!result.ok) throw new Error(`command.execute failed: ${result.error.code}: ${result.error.message}`)
     if (!result.value.matched) return { kind: 'error', text: `unknown or malformed command: ${line}` }
-    const detached = result.value.result
-    return detached === undefined
-      ? { kind: 'success' }
-      : { kind: detached.kind, ...(detached.text !== undefined ? { text: detached.text } : {}) }
+    return { kind: 'success' }
   }
 
   /**
-   * Fire-and-forget execute for the internal ('handled') paths. The detached
-   * result surfaces as a notice routed to the triggering session's composer,
-   * so a late result lands on its own session after a switch.
+   * Fire-and-forget execute for the internal ('handled') paths. Outcomes are
+   * NOT surfaced here: the host executor durably logs the command lifecycle
+   * (`command/run`/`command/done`), and the mux-broadcast events render as a
+   * persistent flow node on every tab. Only a transport/admission failure —
+   * which never entered a handler and therefore never logged — falls back to
+   * the composer notice as immediate feedback.
    */
   private runDetached(desc: CommandDescriptor, session: ClientSessionContext, line: string): void {
     void this.execute(session, line).then(
       (outcome) => {
-        if (outcome.kind === 'error') this.noticeFor(session.sessionId, desc.name, 'error', outcome.text ?? `/${desc.name} failed`)
-        else if (outcome.text !== undefined) this.noticeFor(session.sessionId, desc.name, 'info', outcome.text)
+        // matched:false maps to an error outcome with no logged lifecycle.
+        if (outcome.kind === 'error') this.noticeFor(session.sessionId, 'error', outcome.text ?? `/${desc.name} failed`)
       },
       (error: unknown) => {
-        this.noticeFor(session.sessionId, desc.name, 'error', error instanceof Error ? error.message : String(error))
+        this.noticeFor(session.sessionId, 'error', error instanceof Error ? error.message : String(error))
       },
     )
   }
@@ -270,8 +278,8 @@ export class CommandService extends Service implements CommandServiceContract {
     })
   }
 
-  /** Route a detached result to the session's composer notice channel (scope gone = attempt died with it). */
-  private noticeFor(id: SessionId, _name: string, level: 'info' | 'error', text: string): void {
+  /** Route an admission/transport failure to the session's composer notice channel (scope gone = attempt died with it). */
+  private noticeFor(id: SessionId, level: 'info' | 'error', text: string): void {
     const actx = this.scopeFor(id)
     if (actx === undefined) return
     const conversation = actx.get('conversation')

packages/client/ui-command/tests/service.spec.ts

@@ -31,7 +31,7 @@ const S2_CMDS: CommandDescriptor[] = [
   { name: 'attach', description: 'scoped shadow', input: { hint: 'path' } },
 ]
 
-type ExecuteValue = { matched: boolean; result?: { kind: 'success' | 'error'; text?: string } }
+type ExecuteValue = { matched: boolean }
 
 interface BenchOptions {
   /** Scripted catalog per list payload; default serves the fixed catalogs by session. */
@@ -361,16 +361,18 @@ describe('matchEnter (enter column)', () => {
 })
 
 describe('execute payload', () => {
-  it('claim.submit addresses the session and maps the detached result', async () => {
+  it('claim.submit addresses the session; admitted outcomes stay off the composer (flow card owns them)', async () => {
     const { source, warm, executeCalls } = await bench({
-      execute: () => Promise.resolve({ matched: true, result: { kind: 'success', text: 'goal set' } }),
+      execute: () => Promise.resolve({ matched: true }),
     })
     await warm(proj('s1'))
     const outcome = source.matchSpace!(proj('s1'), '/goal')
     if (outcome === undefined || outcome === 'handled' || !('claim' in outcome)) throw new Error('expected claim')
     const settled = await outcome.claim.submit('ship it', new Context())
     expect(executeCalls).toEqual([{ sessionId: sid('s1'), line: '/goal ship it' }])
-    expect(settled).toEqual({ kind: 'success', text: 'goal set' })
+    // Pure admission: no outcome text ever rides the submit result — the
+    // durable command lifecycle events render the outcome in the flow.
+    expect(settled).toEqual({ kind: 'success' })
   })
 
   it('maps matched:false to an error outcome and a matched bare result to success', async () => {
@@ -389,33 +391,29 @@ describe('execute payload', () => {
   })
 })
 
-describe('detached result notices', () => {
+describe('detached admission notices', () => {
   const flush = () => new Promise(resolve => setTimeout(resolve, 0))
 
-  it('success text → info; error result → error; rejection → error, all on the triggering session', async () => {
-    let mode: 'info' | 'error' | 'reject' = 'info'
+  it('admitted outcomes stay silent; admission miss and transport rejection notice as errors', async () => {
+    let mode: 'admitted' | 'miss' | 'reject' = 'admitted'
     const { source, mint, warm, notices } = await bench({
       execute: () => {
         if (mode === 'reject') return Promise.reject(new Error('network down'))
-        return Promise.resolve({
-          matched: true,
-          result: mode === 'info'
-            ? { kind: 'success' as const, text: 'compacted 12 messages' }
-            : { kind: 'error' as const, text: 'plan mode refused' },
-        })
+        return Promise.resolve({ matched: mode === 'admitted' })
       },
     })
     mint('s1')
     await warm(proj('s1'))
+    // Admitted: the durable lifecycle events own the outcome — no notice.
     menuPick(source, 'plan', proj('s1'))
     await flush()
-    expect(notices).toEqual([{ scope: sid('s1'), level: 'info', text: 'compacted 12 messages' }])
+    expect(notices).toEqual([])
 
-    notices.length = 0
-    mode = 'error'
+    // Admission miss (matched:false): immediate composer feedback stays.
+    mode = 'miss'
     await source.matchEnter!(proj('s1'), '/plan', new AbortController().signal)
     await flush()
-    expect(notices).toEqual([{ scope: sid('s1'), level: 'error', text: 'plan mode refused' }])
+    expect(notices).toEqual([{ scope: sid('s1'), level: 'error', text: 'unknown or malformed command: /plan' }])
 
     notices.length = 0
     mode = 'reject'
@@ -424,9 +422,9 @@ describe('detached result notices', () => {
     expect(notices).toEqual([{ scope: sid('s1'), level: 'error', text: 'network down' }])
   })
 
-  it('success without text stays silent; a torn-down scope drops the notice', async () => {
+  it('a torn-down scope drops the failure notice', async () => {
     const { source, warm, notices } = await bench({
-      execute: () => Promise.resolve({ matched: true, result: { kind: 'success' as const, text: 'orphan' } }),
+      execute: () => Promise.reject(new Error('orphan failure')),
     })
     await warm(proj('ghost')) // never minted: scopeFor misses
     menuPick(source, 'plan', proj('ghost'))

packages/client/ui-conversation/package.json

@@ -49,6 +49,8 @@
   },
   "devDependencies": {
     "@deepseek-ai/dsh-client-runtime": "workspace:^",
+    "@deepseek-ai/dsh-session-projection": "workspace:^",
+    "@deepseek-ai/dsh-tool-todo": "workspace:^",
     "@deepseek-ai/dsh-client-ui-layout": "workspace:^",
     "@deepseek-ai/dsh-client-ui-primitives": "workspace:^",
     "@deepseek-ai/dsh-client-ui-slash": "workspace:^",

packages/client/ui-conversation/src/client/apply.ts

@@ -159,7 +159,10 @@ export function apply(ctx: Context): void {
     id: 'chat',
     order: 0,
     label: 'Chat',
-    children: { 'conversation.chat.toolview': { kind: 'keyed', scope: 'session' } },
+    children: {
+      'conversation.chat.toolview': { kind: 'keyed', scope: 'session' },
+      'conversation.chat.commandview': { kind: 'keyed', scope: 'session' },
+    },
     store: chatStore,
     inject: (sessionId: SessionId, actions: BoundActions<typeof chatStore>): ChatViewInjected => {
       const scoped = scopedConversation(sessions, sessionId)

packages/client/ui-conversation/src/client/chat/ChatView.tsx

@@ -20,13 +20,14 @@ import {
   memo, useLayoutEffect, useMemo, useRef, useState, type ReactNode,
 } from 'react'
 import type {
-  CodeSubCall, ConversationNode, ConversationSnapshot, RunningToolCall, ToolResultNode,
+  CodeSubCall, CommandNode, ConversationNode, ConversationSnapshot, RunningToolCall, ToolResultNode,
 } from '@deepseek-ai/dsh-client-runtime/client'
 import type { SnapshotSelectorHook } from '@deepseek-ai/dsh-client-ui-slots'
 import { IconChevronDownOutline14 } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { ChatViewSlotProps } from '../contract/slots.ts'
 import { deriveChatFlow, type ChatFlowItem } from './chat-flow.ts'
 import { AssistantMarkdown } from './AssistantMarkdown.tsx'
+import { GenericCommandCard } from './GenericCommandCard.tsx'
 import { GenericToolCard } from './GenericToolCard.tsx'
 import { MessageItem } from './MessageItem.tsx'
 import { PendingCard } from './PendingCard.tsx'
@@ -151,6 +152,24 @@ const ToolGroup = memo(function ToolGroup({ renderSlot, results, openFile, selec
   )
 })
 
+/** One command lifecycle row: keyed dispatch on the command name with the
+ *  generic card as the render-site fallback (zero registration required). A
+ *  run-less cross-window node has no name and always lands on the fallback. */
+const CommandRow = memo(function CommandRow({ renderSlot, node }: {
+  renderSlot: RenderToolRow
+  node: CommandNode
+}) {
+  const owner = useMemo(() => ({ node }), [node])
+  return (
+    <div className={css.callRow}>
+      {renderSlot('conversation.chat.commandview', owner, {
+        entryKey: node.name ?? '',
+        fallback: <GenericCommandCard {...owner} />,
+      })}
+    </div>
+  )
+})
+
 /** Turn loader: one row of four 2.5px pixels (half a notch above the StateDot
  *  2px cell, same blue) chasing left to right with a stepped trail — flat
  *  keyframe holds, no tweening, no rotation. Phase offsets come from
@@ -315,6 +334,9 @@ export function ChatView({ useSession, useSessions, useStore, renderSlot, sessio
     if (node.kind === 'assistant') {
       return <AssistantMarkdown key={item.key} blocks={node.blocks} streaming={false} interrupted={node.interrupted} />
     }
+    if (node.kind === 'command') {
+      return <CommandRow key={item.key} renderSlot={renderSlot} node={node} />
+    }
     /* v8 ignore next -- tool-result never reaches here: deriveChatFlow folds them into groups. */
     if (node.kind === 'tool-result') return null
     return <MessageItem key={item.key} node={node} />

packages/client/ui-conversation/src/client/chat/GenericCommandCard.tsx

@@ -0,0 +1,38 @@
+// GenericCommandCard: the default command row — a stripped-down
+// GenericToolCard rendering the dispatched command line and the settlement
+// text. Supplied by the chat view as the keyed commandview slot's render-site
+// fallback (an unregistered command name lands here); registrants may compose
+// it as a base, feeding the same owner payload through.
+
+import { ToolRow } from './ToolRow.tsx'
+import type { ToolRowState } from '../contract/tool-call-model.ts'
+import type { CommandRowOwnerProps } from '../contract/slots.ts'
+import { IconApiOutline14 } from '@deepseek-ai/dsh-client-ui-primitives'
+
+/** Node state → row state semantic (running while unsettled; outcome kind after). */
+function stateOf(outcome: CommandRowOwnerProps['node']['outcome']): ToolRowState {
+  if (outcome === null) return 'running'
+  return outcome.kind === 'error' ? 'error' : 'ok'
+}
+
+export function GenericCommandCard({ node }: CommandRowOwnerProps) {
+  const text = node.outcome?.text
+  const summary = node.outcome === null
+    ? '执行中…'
+    : text ?? (node.outcome.kind === 'error' ? '命令失败' : '已完成')
+  // Display line rebuilt from the structured payload (args carries its own
+  // separator whitespace verbatim); a cross-window node whose run page fell
+  // out of the window has neither.
+  const title = node.name === null ? '命令' : `/${node.name}${node.args ?? ''}`
+  return (
+    <ToolRow
+      variant="others"
+      icon={<IconApiOutline14 size={16} />}
+      title={title}
+      summary={summary}
+      // Expandable only when the outcome text overflows a one-line summary.
+      body={text !== undefined && text.includes('\n') ? text : null}
+      state={stateOf(node.outcome)}
+    />
+  )
+}

packages/client/ui-conversation/src/client/contract/slots.ts

@@ -3,7 +3,7 @@ import type { ReactNode, RefObject } from 'react'
 import type {
   InjectFace, MaybeSnapshotSelectorHook, PropsRenderSlots, PropsRuntime, PropsStore, SnapshotSelectorHook,
 } from '@deepseek-ai/dsh-client-ui-slots'
-import type { ConversationSnapshot, ObservableSnapshot, PendingInteraction, SessionId, ToolCallBlock, WorkspaceId } from '@deepseek-ai/dsh-client-runtime/client'
+import type { CommandNode, ConversationSnapshot, ObservableSnapshot, PendingInteraction, SessionId, ToolCallBlock, WorkspaceId } from '@deepseek-ai/dsh-client-runtime/client'
 import type {} from '@deepseek-ai/dsh-client-ui-layout/client'
 import type { ComposerKeyboard, InputActions, InputNotice, InputState } from '../input/contract.ts'
 import type { createChatStore } from '../stores.ts'
@@ -33,6 +33,15 @@ declare module '@deepseek-ai/dsh-client-ui-slots' {
      * `fallback` for unregistered tools.
      */
     'conversation.chat.toolview': { kind: 'keyed'; scope: 'session'; owner: ToolRowOwnerProps }
+    /**
+     * The chat view's per-command row hole: keyed dispatch on the command
+     * name (`command/run.name`; a run-less cross-window node has none and
+     * always lands on the fallback). Declared by the chat view entry; the
+     * render site dispatches via `entryKey: name` with GenericCommandCard as
+     * the `fallback` — a slash command renders durably with zero
+     * registration, and a domain upgrades by registering one row component.
+     */
+    'conversation.chat.commandview': { kind: 'keyed'; scope: 'session'; owner: CommandRowOwnerProps }
     /**
      * The composer takeover chain: entries are selector-routed replacements
      * of the default InputBar. Declared by this package's 'conversation'
@@ -161,6 +170,22 @@ export interface ToolRowOwnerProps {
  */
 export type ToolRowProps = PropsRuntime<'conversation.chat.toolview'>
 
+/**
+ * Owner share of the per-command row slot: the frozen {@link CommandNode}
+ * slice off the snapshot (cache-stable reference — memo premise). The node
+ * carries the whole lifecycle (structured name/args, pairing id,
+ * outcome-or-executing), so a
+ * registrant needs no second data channel; domain state arrives through its
+ * own projection cell.
+ */
+export interface CommandRowOwnerProps {
+  /** Folded command lifecycle node (run + optional done). */
+  node: CommandNode
+}
+
+/** Full props of a registered command-row component (same shape rule as {@link ToolRowProps}). */
+export type CommandRowProps = PropsRuntime<'conversation.chat.commandview'>
+
 /**
  * Base props of a conversation view entry: the framework standard kit for the
  * session-scope 'conversation.view' slot (useSession narrowed to the
@@ -296,9 +321,9 @@ export interface ChatViewInjected {
   loadOlder: () => void
 }
 
-/** Full chat-view component props: runtime share & the declared toolview hole's render share & store share & injected share. */
+/** Full chat-view component props: runtime share & the declared toolview/commandview holes' render share & store share & injected share. */
 export type ChatViewSlotProps =
-  PropsRuntime<'conversation.view'> & PropsRenderSlots<'conversation.chat.toolview'>
+  PropsRuntime<'conversation.view'> & PropsRenderSlots<'conversation.chat.toolview' | 'conversation.chat.commandview'>
   & PropsStore<ChatStore> & ChatViewInjected
 
 /**

packages/client/ui-conversation/src/client/index.ts

@@ -13,7 +13,8 @@ export type {
 } from './contract/views.ts'
 export type { ToolCallBlock } from './contract/tool-call-model.ts'
 export type {
-  ChatStore, ChatViewInjected, ChatViewSlotProps, ComposerBarInjected, ComposerChainProps, ConversationInjected,
+  ChatStore, ChatViewInjected, ChatViewSlotProps, CommandRowOwnerProps, CommandRowProps, ComposerBarInjected,
+  ComposerChainProps, ConversationInjected,
   ConversationSessionInjected, ConversationSlotProps, ConvViewOwnerProps, ConvViewProps, DetailsInjected, DetailsSlotProps,
   EmptyWorkspaceOwnerProps, ToolRowOwnerProps, ToolRowProps,
 } from './contract/slots.ts'

packages/client/ui-conversation/src/client/skeleton/TodoPanel.tsx

@@ -8,7 +8,11 @@
 import { useId, useState } from 'react'
 import type { Context } from 'cordis'
 import type { PropsRuntime } from '@deepseek-ai/dsh-client-ui-slots'
-import type { TodoItem } from '@deepseek-ai/dsh-client-runtime/client'
+// The domain's client-namespace pure-type outlet: one import edge delivers
+// the `todos` projection-key merge (single source, no consumer-side restated
+// declare) and the payload type. Type-only by construction — the outlet is
+// free of host value imports, so no host Context merge enters this program.
+import type { TodoItem } from '@deepseek-ai/dsh-tool-todo/client'
 import { IconChevronDownOutline14, IconChevronUpOutline14 } from '@deepseek-ai/dsh-client-ui-primitives'
 import css from './TodoPanel.module.css'
 
@@ -115,10 +119,10 @@ export function TodoPanel({ todos }: TodoPanelProps) {
 /** Full props of a dock entry: InputZone owner share + session standard kit + global seat. */
 export type TodoDockProps = PropsRuntime<'conversation.input.dock'>
 
-/** Dock adapter: selects the plan off the session snapshot and hands the strip a plain list. */
-export function TodoDock({ useSession }: TodoDockProps) {
-  const todos = useSession(s => s.todos)
-  return <TodoPanel todos={todos} />
+/** Dock adapter: reads the host-computed 'todos' projection (whole list; absent or null renders nothing). */
+export function TodoDock({ useProjection }: TodoDockProps) {
+  const todos = useProjection('todos')
+  return <TodoPanel todos={todos ?? []} />
 }
 
 /**

packages/client/ui-conversation/tests/chat-code-subcalls.spec.tsx

@@ -56,7 +56,7 @@ function snapshotWith(
 ): ConversationSnapshot {
   return {
     sessionId: SID, nodes, foldDegraded: false, partial: null, runningCalls, codeDispatches,
-    pending: [], queue: [], todos: [], running: runningCalls.length > 0, composerPhase: 'active', removed: false,
+    pending: [], queue: [], running: runningCalls.length > 0, composerPhase: 'active', removed: false,
     openState: 'open', openError: null,
     hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   }

packages/client/ui-conversation/tests/chat-stats-bash-sample.spec.tsx

@@ -27,7 +27,7 @@ const assistant = (seq: number, turn: number, usage?: unknown): AssistantMessage
 function snapshotBase(): ConversationSnapshot {
   return {
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
     hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   }
 }

packages/client/ui-conversation/tests/chat-toolview-slot.spec.tsx

@@ -43,7 +43,7 @@ const toolResult = (seq: number, callId: string, name: string, args = '{"command
 function snapshotWith(nodes: ToolResultNode[]): ConversationSnapshot {
   return {
     sessionId: SID, nodes, foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
     hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   }
 }

packages/client/ui-conversation/tests/chat-view.spec.tsx

@@ -7,7 +7,7 @@ import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { Profiler } from 'react'
 import { act, cleanup, fireEvent, render } from '@testing-library/react'
 import type {
-  AssistantMessageNode, ConversationNode, ConversationSnapshot, RunningToolCall, SessionId,
+  AssistantMessageNode, CommandNode, ConversationNode, ConversationSnapshot, RunningToolCall, SessionId,
   SessionListState, ToolResultNode, UserMessageNode, WorkspaceListState,
 } from '@deepseek-ai/dsh-client-runtime/client'
 import { bindSnapshotSelector } from '@deepseek-ai/dsh-client-web-react'
@@ -30,7 +30,7 @@ const SID = 's1' as SessionId
 function snapshotBase(): ConversationSnapshot {
   return {
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
     hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   }
 }
@@ -106,6 +106,7 @@ function makeHarness(init?: Partial<ConversationSnapshot>) {
     useSession: bindSnapshotSelector(source),
     useSessions: emptySessions(),
     useWorkspaces: emptyWorkspaces(),
+    useProjection: (() => undefined),
     useInput: (() => { throw new Error('unused') }),
     inputActions: { setDraft: () => {}, submit: () => {} },
     useStore: bindSnapshotSelector(chat),
@@ -395,4 +396,41 @@ describe('ChatView', () => {
     const view = render(<h.ChatView {...h.props} />)
     expect(view.getByText(/等待审批/)).toBeTruthy()
   })
+
+  it('renders command nodes as durable rows: settled text, error state, executing spinner, run-less soft-fall', () => {
+    const command = (over: Partial<CommandNode>): CommandNode => ({
+      kind: 'command', seq: 5, time: 5_000, commandId: 'cmd-1' as CommandNode['commandId'],
+      name: 'plan', args: '', outcome: { kind: 'success', text: '已进入 plan mode' },
+      ...over,
+    })
+    // Settled success: the command line is the title, the outcome text the summary.
+    const settled = makeHarness({ nodes: [user(1, 'hi'), command({})] })
+    const view = render(<settled.ChatView {...settled.props} />)
+    expect(view.getByText('/plan')).toBeTruthy()
+    expect(view.getByText('已进入 plan mode')).toBeTruthy()
+
+    // Error outcome flips the row state; a text-less error gets the default copy.
+    const failed = makeHarness({
+      nodes: [command({ seq: 6, commandId: 'cmd-2' as CommandNode['commandId'], outcome: { kind: 'error' } })],
+    })
+    const fv = render(<failed.ChatView {...failed.props} />)
+    expect(fv.container.querySelector('[data-state="error"]')).not.toBeNull()
+    expect(fv.getByText('命令失败')).toBeTruthy()
+
+    // Still executing: running state with the executing copy.
+    const executing = makeHarness({
+      nodes: [command({ seq: 7, commandId: 'cmd-3' as CommandNode['commandId'], outcome: null })],
+    })
+    const xv = render(<executing.ChatView {...executing.props} />)
+    expect(xv.container.querySelector('[data-state="running"]')).not.toBeNull()
+    expect(xv.getByText('执行中…')).toBeTruthy()
+
+    // Cross-window soft-fall (run page truncated): generic title, outcome preserved.
+    const orphan = makeHarness({
+      nodes: [command({ seq: 8, commandId: 'cmd-4' as CommandNode['commandId'], name: null, args: null, outcome: { kind: 'success' } })],
+    })
+    const ov = render(<orphan.ChatView {...orphan.props} />)
+    expect(ov.getByText('命令')).toBeTruthy()
+    expect(ov.getByText('已完成')).toBeTruthy()
+  })
 })

packages/client/ui-conversation/tests/gate-branch-tails.spec.tsx

@@ -19,7 +19,7 @@ const SID = 's1' as SessionId
 function snapshotBase(): ConversationSnapshot {
   return {
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
     hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   }
 }
@@ -76,6 +76,7 @@ describe('render branch tails', () => {
         useSession={bindSnapshotSelector({ getSnapshot: () => snap, subscribe: () => () => {} })}
         useSessions={bindSnapshotSelector(emptyList)}
         useWorkspaces={bindSnapshotSelector(emptyWorkspaces)}
+        useProjection={(() => undefined)}
         useInput={(() => { throw new Error('unused') })}
         inputActions={{ setDraft: () => {}, submit: () => {} }}
         useStore={bindSnapshotSelector(chat)}
@@ -111,6 +112,7 @@ describe('render branch tails', () => {
         useSession={bindSnapshotSelector({ getSnapshot: () => snap, subscribe: () => () => {} })}
         useSessions={bindSnapshotSelector(emptyList)}
         useWorkspaces={bindSnapshotSelector(emptyWorkspaces)}
+        useProjection={(() => undefined)}
         useInput={(() => { throw new Error('unused') })}
         inputActions={{ setDraft: () => {}, submit: () => {} }}
         useStore={bindSnapshotSelector(chat)}

packages/client/ui-conversation/tests/input-bar.spec.tsx

@@ -21,7 +21,7 @@ const SID = 's1' as SessionId
 function snapshotOf(overrides: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
   return {
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
     openState: 'open', openError: null, hasMore: false, loadingOlder: false,
     promptError: null, blank: false, lastAgentError: null,
     ...overrides,
@@ -88,6 +88,7 @@ function bench(over?: BenchOptions) {
       items: [], state: 'idle', phase: 'ready', error: null,
       baselinesReady: true, recentWorkspaceId: undefined,
     })),
+    useProjection: (() => undefined),
     useInput: bindSnapshotSelector(shell.state),
     inputActions: shell.actions,
     keyboard: shell,

packages/client/ui-conversation/tests/input-matrix.spec.tsx

@@ -24,7 +24,7 @@ const SID = 's1' as SessionId
 function mountBar(shell: SessionInputShell, over?: { running?: boolean; disabled?: boolean }) {
   const session = createSnapshotStore<ConversationSnapshot>({
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: over?.running ?? false, composerPhase: 'active',
+    pending: [], queue: [], running: over?.running ?? false, composerPhase: 'active',
     removed: over?.disabled ?? false, openState: 'open', openError: null, hasMore: false,
     loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   })
@@ -39,6 +39,7 @@ function mountBar(shell: SessionInputShell, over?: { running?: boolean; disabled
       items: [], state: 'idle', phase: 'ready', error: null,
       baselinesReady: true, recentWorkspaceId: undefined,
     })),
+    useProjection: (() => undefined),
     useInput: bindSnapshotSelector(shell.state),
     inputActions: shell.actions,
     keyboard: shell,

packages/client/ui-conversation/tests/input-scenarios.spec.tsx

@@ -110,7 +110,7 @@ async function scopedBench(register?: (slash: SlashService) => void) {
   const wiring = shell
   const sessionStore = createSnapshotStore<ConversationSnapshot>({
     sessionId, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
     openState: 'open', openError: null, hasMore: false, loadingOlder: false,
     promptError: null, blank: false, lastAgentError: null,
   })
@@ -125,6 +125,7 @@ async function scopedBench(register?: (slash: SlashService) => void) {
       items: [], state: 'idle', phase: 'ready', error: null,
       baselinesReady: true, recentWorkspaceId: undefined,
     })),
+    useProjection: (() => undefined),
     useInput: bindSnapshotSelector(shell.state),
     inputActions: shell.actions,
     keyboard: shell,

packages/client/ui-conversation/tests/queue-dock.spec.tsx

@@ -19,7 +19,7 @@ const SID = 's1' as SessionId
 function snapshotWith(queue: QueuedMessage[]): ConversationSnapshot {
   return {
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue, todos: [], running: true, composerPhase: 'active', removed: false, openState: 'open', openError: null,
+    pending: [], queue, running: true, composerPhase: 'active', removed: false, openState: 'open', openError: null,
     hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null,
   }
 }
@@ -53,6 +53,7 @@ function kitFor(snapshot: ConversationSnapshot) {
     sessionId: SID,
     useSessions: (() => { throw new Error('unused') }) as unknown as SnapshotSelectorHook<SessionListState>,
     useWorkspaces: (() => { throw new Error('unused') }) as never,
+    useProjection: (() => undefined) as never,
     useInput: (() => { throw new Error('unused') }) as never,
     inputActions: { setDraft: () => {}, submit: () => {} } as never,
     session: snapshot,

packages/client/ui-conversation/tests/skeleton.spec.tsx

@@ -48,7 +48,7 @@ const workspaceState = (items: readonly WorkspaceView[]): WorkspaceListState =>
 function conversationSnapshot(overrides: Partial<ConversationSnapshot> = {}): ConversationSnapshot {
   return {
     sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
-    pending: [], queue: [], todos: [], running: false, composerPhase: 'active', removed: false,
+    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
     openState: 'open', openError: null, hasMore: false, loadingOlder: false,
     promptError: null, blank: false, lastAgentError: null,
     ...overrides,
@@ -93,6 +93,7 @@ function mount(
           useSession={useSession}
           useSessions={props.useSessions}
           useWorkspaces={props.useWorkspaces}
+          useProjection={(() => undefined)}
           useInput={useInput}
           inputActions={inputActions}
           useStore={bindSnapshotSelector(chat)}
@@ -115,6 +116,7 @@ function mount(
           useSession={useSession}
           useSessions={props.useSessions}
           useWorkspaces={props.useWorkspaces}
+          useProjection={(() => undefined)}
           useInput={useInput}
           inputActions={inputActions}
           keyboard={wiring}
@@ -135,6 +137,7 @@ function mount(
     useSession,
     useSessions: bindSnapshotSelector(sessions),
     useWorkspaces: bindSnapshotSelector(workspaces),
+    useProjection: (() => undefined),
     useInput,
     inputActions,
     renderSlot,

packages/client/ui-conversation/tests/todo-panel.spec.tsx

@@ -118,20 +118,23 @@ describe('TodoPanel', () => {
   })
 })
 
-/** Dock props stub: the adapter reads useSession only; the rest of the owner share is unused. */
-function dockProps(store: ReturnType<typeof createSnapshotStore<{ todos: readonly TodoItem[] }>>): TodoDockProps {
-  return { useSession: bindSnapshotSelector(store) } as unknown as TodoDockProps
+/** Dock props stub: the adapter reads the 'todos' projection only; the rest of the owner share is unused. */
+function dockProps(store: ReturnType<typeof createSnapshotStore<{ value: readonly TodoItem[] | null | undefined }>>): TodoDockProps {
+  const useProjection = (_key: string, selector?: (v: unknown) => unknown) =>
+    bindSnapshotSelector(store)(s => (selector ?? (v => v))(s.value))
+  return { useProjection } as unknown as TodoDockProps
 }
 
 describe('TodoDock', () => {
-  it('selects the plan off the session snapshot and follows later writes', () => {
-    const store = createSnapshotStore<{ todos: readonly TodoItem[] }>({ todos: [] })
+  it('reads the host-computed todos projection and follows pushed updates', () => {
+    const store = createSnapshotStore<{ value: readonly TodoItem[] | null | undefined }>({ value: undefined })
     render(<TodoDock {...dockProps(store)} />)
+    // Capability absent (no baseline/frame yet) renders nothing.
     expect(screen.queryByTestId('todo-panel')).toBeNull()
-    act(() => { store.set({ todos: LIST }) })
+    act(() => { store.set({ value: LIST }) })
     expect(screen.getByText('1/3 tasks · 1 in progress')).toBeTruthy()
-    // A rollback to the empty list retires the strip (the panel owns no data).
-    act(() => { store.set({ todos: [] }) })
+    // The pre-first-write whole value (null) retires the strip (the panel owns no data).
+    act(() => { store.set({ value: null }) })
     expect(screen.queryByTestId('todo-panel')).toBeNull()
   })
 

packages/client/ui-conversation/tsconfig.json

@@ -23,6 +23,12 @@
     {
       "path": "../runtime"
     },
+    {
+      "path": "../../session-projection/session-projection"
+    },
+    {
+      "path": "../../todo/tool-todo"
+    },
     {
       "path": "../ui-slash"
     },

packages/client/ui-question/tests/question-composer.spec.tsx

@@ -25,6 +25,7 @@ const kit = {
   useSession: (() => { throw new Error('unused') }) as unknown as SnapshotSelectorHook<ConversationSnapshot>,
   useSessions: (() => { throw new Error('unused') }) as unknown as SnapshotSelectorHook<SessionListState>,
   useWorkspaces: (() => { throw new Error('unused') }) as unknown as SnapshotSelectorHook<WorkspaceListState>,
+  useProjection: (() => undefined) as never,
   useInput: (() => { throw new Error('unused') }) as never,
   inputActions: { setDraft: () => { throw new Error('unused') }, submit: () => { throw new Error('unused') } } as never,
 }

packages/client/ui-slots/src/renderer.ts

@@ -44,6 +44,15 @@ export interface SessionMaybeProvideInfo {
   hooks: Record<string, HostObservable<unknown> | undefined>
   /** Static plain-member roster; values are undefined with the session. */
   props: Record<string, unknown>
+  /**
+   * Key-addressed projection value sources (the useProjection framework seat,
+   * session-projection RFC). Unlike `hooks`, the key space is open — values
+   * arrive from host-computed push frames — so the render side binds per
+   * resolved key instead of per static roster member. Faces are always
+   * defined per key (absence is an `undefined` snapshot); the whole member is
+   * absent with the session.
+   */
+  projections?: { faceOf(key: string): HostObservable<unknown> } | undefined
 }
 
 /** Definite per-session standard props resolved for strict session slots. */

packages/client/ui-trajectory/tests/views.spec.tsx

@@ -77,6 +77,7 @@ function standaloneProps(nodes: ConversationSnapshot['nodes']): ConvViewProps {
     useSession: fakeSession(nodes).useSession,
     useSessions: emptySessions(),
     useWorkspaces: emptyWorkspaces(),
+    useProjection: (() => undefined) as never,
   } as unknown as ConvViewProps
 }
 
@@ -135,6 +136,7 @@ function mount(slots: SlotsService, nodes: ConversationSnapshot['nodes'] = NODES
       useSession={useSession}
       useSessions={emptySessions()}
       useWorkspaces={emptyWorkspaces()}
+      useProjection={(() => undefined)}
       useStore={bindSnapshotSelector(chat)}
       actions={chat.actions}
       renderSlot={renderSlot}
@@ -330,6 +332,7 @@ describe('deriveSubSpans (waterfall lanes)', () => {
       useSession: bindSnapshotSelector(store) as unknown as UseSession<ConversationSnapshot>,
       useSessions: emptySessions(),
       useWorkspaces: emptyWorkspaces(),
+      useProjection: (() => undefined) as never,
     } as unknown as ConvViewProps
     const view = render(createElement(WaterfallView as FC<ConvViewProps>, props))
     const lane = view.container.querySelector('[data-subspan]')
@@ -356,6 +359,7 @@ describe('deriveSubSpans (waterfall lanes)', () => {
       useSession: bindSnapshotSelector(store) as unknown as UseSession<ConversationSnapshot>,
       useSessions: emptySessions(),
       useWorkspaces: emptyWorkspaces(),
+      useProjection: (() => undefined) as never,
     } as unknown as ConvViewProps
     const view = render(createElement(WaterfallView as FC<ConvViewProps>, props))
     const bar = view.container.querySelector('[data-timing="unknown"]')

packages/client/web-react/src/scoped-slots.tsx

@@ -10,7 +10,7 @@ import {
 } from '@deepseek-ai/dsh-client-ui-slots'
 import {
   HostContext, SessionMaybeProvider, SessionProvider, SlotAssemblyError, maybeObservableHook,
-  observableHook, useHost, useSessionMaybeProvideInfo,
+  observableHook, projectionHook, useHost, useSessionMaybeProvideInfo,
 } from './session-provider.tsx'
 
 type InjectedProps = Record<string, unknown>
@@ -238,6 +238,9 @@ function standardKit(
     }
     Object.assign(kit, info.props)
     kit['sessionId'] = info.sessionId
+    // The useProjection seat (fifth framework hook): key-addressed cell
+    // reader, bound per provide bundle (cached by info identity).
+    kit['useProjection'] = projectionHook(info)
   }
   const store = scope === 'session-maybe' && info?.sessionId === undefined
     ? undefined

packages/client/web-react/src/session-provider.tsx

@@ -83,6 +83,39 @@ function useAbsentSnapshot<S>(_selector: (snapshot: never) => S, _equal?: (a: S,
   return undefined
 }
 
+/**
+ * The useProjection framework seat (session-projection RFC), one bound
+ * function per provide bundle (cached by info identity — components may hold
+ * it across renders). Key-addressed: the key resolves a per-session value
+ * face off the projection store; the bound selector hook comes from the same
+ * per-source cache as every other kit hook, so exactly one uSES subscription
+ * runs per call and the subscribe reference stays stable per key. A key no
+ * baseline or frame has carried (or a no-session bundle) reads `undefined` —
+ * capability absence — keeping the hook order constant.
+ */
+export function projectionHook(info: SessionMaybeProvideInfo): (
+  key: string, selector?: (value: unknown) => unknown, eq?: (a: unknown, b: unknown) => boolean,
+) => unknown {
+  let hook = projectionHookCache.get(info)
+  if (hook === undefined) {
+    hook = (key, selector, eq) => {
+      // The no-session (faceless) branch binds the shared absent source so
+      // the caller's selector still runs over `undefined` (absence flows
+      // through the selector) and the uSES call count stays constant.
+      const useValue = observableHook(info.projections?.faceOf(key) ?? absentSource)
+      // Whole values are finished wire payloads (reference changes only when
+      // a frame or baseline lands), so the identity selector needs no
+      // equality function.
+      return useValue(selector ?? (value => value), eq)
+    }
+    projectionHookCache.set(info, hook)
+  }
+  return hook
+}
+const projectionHookCache = new WeakMap<SessionMaybeProvideInfo, (
+  key: string, selector?: (value: unknown) => unknown, eq?: (a: unknown, b: unknown) => boolean,
+) => unknown>()
+
 /**
  * Root-level binding provider. It follows current selection without a key, so
  * session-maybe entries retain their React identity while the context value

packages/client/web-react/tests/use-projection.spec.tsx

@@ -0,0 +1,128 @@
+// @vitest-environment jsdom
+/**
+ * useProjection standard-kit delivery (session-projection RFC): the fifth
+ * framework hook seat rides the same provide channel as useSession — a
+ * session slot component receives `useProjection` in its kit, key-addressed
+ * over the bundle's projection face; unresolved keys (no value, no face, no
+ * session) uniformly read `undefined`; live value changes re-render; the
+ * selector overload runs over the whole value.
+ */
+import { describe, expect, it } from 'vitest'
+import { act, render } from '@testing-library/react'
+import type { SessionMaybeProvideInfo, StoredEntry } from '@deepseek-ai/dsh-client-ui-slots'
+import { createSlotRenderer, type SlotRendererHost } from '@deepseek-ai/dsh-client-web-react'
+
+function observable<T>(initial: T) {
+  let value = initial
+  const subs = new Set<() => void>()
+  return {
+    getSnapshot: () => value,
+    subscribe: (fn: () => void) => { subs.add(fn); return () => { subs.delete(fn) } },
+    set: (next: T) => { value = next; for (const fn of [...subs]) fn() },
+  }
+}
+
+type UseProjectionProp = (key: string, selector?: (v: unknown) => unknown) => unknown
+
+function makeHost() {
+  const absentInfo: SessionMaybeProvideInfo = { sessionId: undefined, hooks: { session: undefined }, props: {} }
+  const provide = observable<SessionMaybeProvideInfo>(absentInfo)
+  const cells = new Map<string, ReturnType<typeof observable<unknown>>>()
+  /** Store-parallel face: always defined per key; an unseen key snapshots undefined. */
+  const absent = { getSnapshot: () => undefined, subscribe: () => () => {} }
+  const sessionEntries: StoredEntry[] = []
+  let withFace = true
+  const rootEntry: StoredEntry = {
+    component: (props: { renderSlot: (key: string, owner: object) => React.ReactNode }) =>
+      <>{props.renderSlot('k.session', {})}</>,
+    options: {},
+    children: { 'k.session': { kind: 'single', scope: 'session' } },
+  }
+  const info = (id: string): SessionMaybeProvideInfo => ({
+    sessionId: id,
+    hooks: { session: { getSnapshot: () => ({ sid: id }), subscribe: () => () => {} } },
+    props: {},
+    ...(withFace ? { projections: { faceOf: (key: string) => cells.get(key) ?? absent } } : {}),
+  })
+  const host: SlotRendererHost = {
+    subscribe: () => () => {},
+    getVersion: () => 0,
+    entriesOf: key => key === 'root' ? [rootEntry] : sessionEntries,
+    specOf: key => key === 'k.session' ? { kind: 'single', scope: 'session' } : undefined,
+    isLive: () => true,
+    storeOf: () => undefined,
+    sessions: {
+      list: observable<unknown>({ ids: [] }),
+      provideInfo: provide,
+    },
+    workspaces: { list: observable<unknown>({ items: [] }) },
+  }
+  return {
+    host,
+    cells,
+    // Same driver surface as before the atomic provide source: set(id)
+    // publishes the resolved bundle (or the absent projection) through it.
+    current: { set: (id: string | undefined) => { provide.set(id === undefined ? absentInfo : info(id)) } },
+    dropFace: () => { withFace = false },
+    registerSession: (entry: StoredEntry) => { sessionEntries.push(entry) },
+  }
+}
+
+describe('useProjection standard-kit delivery', () => {
+  it('reads the projected value through the kit, undefined for unresolved keys, and follows live changes', () => {
+    const h = makeHost()
+    const cell = observable<unknown>({ marks: ['a'] })
+    h.cells.set('test/marks', cell)
+    const reads: Record<string, unknown>[] = []
+    h.registerSession({
+      component: (props: { useProjection: UseProjectionProp }) => {
+        reads.push({
+          marks: props.useProjection('test/marks'),
+          ghost: props.useProjection('test/ghost'),
+        })
+        return null
+      },
+      options: {},
+    })
+    render(<>{createSlotRenderer().renderRoot(h.host, {})}</>)
+    act(() => { h.current.set('s1') })
+    expect(reads.at(-1)).toEqual({ marks: { marks: ['a'] }, ghost: undefined })
+    // Live change re-renders with the new whole value.
+    act(() => { cell.set({ marks: ['a', 'b'] }) })
+    expect(reads.at(-1)).toEqual({ marks: { marks: ['a', 'b'] }, ghost: undefined })
+  })
+
+  it('runs the selector overload over the whole value (and over undefined when absent)', () => {
+    const h = makeHost()
+    h.cells.set('test/marks', observable<unknown>({ marks: ['x', 'y'] }))
+    const reads: unknown[] = []
+    h.registerSession({
+      component: (props: { useProjection: UseProjectionProp }) => {
+        reads.push(props.useProjection('test/marks', v => (v as { marks: string[] } | undefined)?.marks.length ?? -1))
+        reads.push(props.useProjection('test/ghost', v => (v === undefined ? 'absent' : 'present')))
+        return null
+      },
+      options: {},
+    })
+    render(<>{createSlotRenderer().renderRoot(h.host, {})}</>)
+    act(() => { h.current.set('s1') })
+    expect(reads.slice(-2)).toEqual([2, 'absent'])
+  })
+
+  it('treats a bundle without the projections face as all-absent (capability absence)', () => {
+    const h = makeHost()
+    h.cells.set('test/marks', observable<unknown>({ marks: ['a'] }))
+    h.dropFace()
+    const reads: unknown[] = []
+    h.registerSession({
+      component: (props: { useProjection: UseProjectionProp }) => {
+        reads.push(props.useProjection('test/marks'))
+        return null
+      },
+      options: {},
+    })
+    render(<>{createSlotRenderer().renderRoot(h.host, {})}</>)
+    act(() => { h.current.set('s1') })
+    expect(reads.at(-1)).toBeUndefined()
+  })
+})